JP6840202B1 - Exhaust gas treatment equipment and water supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust gas treatment device and a water supply method capable of saving the installation space of equipment required for the water supply function without deteriorating the water supply function. An exhaust gas treatment device includes an EGR device that cleans exhaust gas discharged from an engine body of a marine diesel engine with scrubber water and recirculates the washed exhaust gas as a part of the combustion gas. A collection pipe that collects the condensed water generated from the combustion gas that has been pressurized and compressed by the supercharger and cooled by the cooler and the gas pressure due to the combustion gas after cooling, and the condensed water through the collection pipe. A condensing water chamber for storing the gas pressure and accumulating the gas pressure, and a water supply pipe for communicating the condensed water chamber and the condensate water supply destination device are provided. The condensed water is pressure-fed from the condensed water chamber to the supply destination device through the water supply pipe by utilizing the gas pressure accumulated in the condensed water chamber. [Selection diagram] Fig. 1

Description

The present invention relates to an exhaust gas treatment device and a water supply method applied to a marine diesel engine.

In a marine diesel engine mounted on a ship, the exhaust gas emitted from the engine body generally contains harmful substances such as nitrogen oxides (NOx), sulfur oxides (SOx), and soot and dust. Therefore, in order to comply with the exhaust gas regulations required for marine diesel engines, it is necessary to equip marine diesel engines with an exhaust gas treatment device that removes harmful substances in the exhaust gas.

Some such exhaust gas treatment devices employ, for example, a technique of exhaust gas recirculation (EGR: Exhaust Gas Recirculation), which is a method for reducing NOx in exhaust gas (see Patent Documents 1 and 2). In EGR, a part of the exhaust gas discharged from the engine body is washed by the scrubber, and the washed exhaust gas (hereinafter referred to as recirculation gas) is mixed with air and returned to the engine body as combustion gas. .. As a result, in the combustion chamber of the engine body, the generation of NOx due to the combustion of fuel is suppressed, and as a result, the content of NOx in the exhaust gas (that is, the amount of NOx emitted) is reduced.

Further, in the EGR device, the scrubber injects water into the exhaust gas, thereby removing harmful substances such as SOx and soot in the exhaust gas and cleaning the exhaust gas. Such a scrubber is a known technique not only for reducing NOx by EGR but also for removing SOx and soot and dust in the exhaust gas discharged from the chimney.

On the other hand, since the exhaust gas has a high temperature, a part of the water used for cleaning the exhaust gas in the scrubber (hereinafter referred to as scrubber water) is vaporized when it is injected into the scrubber. This vaporized scrubber water flows out as steam together with the recirculated gas into the recirculated gas path from the exhaust gas treatment device to the engine body. Therefore, the scrubber water gradually decreases due to evaporation due to high-temperature exhaust gas and the like. Therefore, in the exhaust gas treatment device, it is necessary to supply water to a necessary place such as a scrubber, thereby replenishing the scrubber water.

Japanese Patent No. 6147786 Japanese Patent No. 5916772

By the way, as described above, when water is supplied to a required part of the exhaust gas treatment device, conventionally, the combustion gas supplied to the engine body (for example, a compressed gas obtained by mixing recirculation gas and air) is cooled. The generated condensed water was stored in a tank in advance, and this condensed water was pumped from the tank by the action of a pump.

However, in the conventional water supply method described above, not only the pump for pumping water, but also the starter and power supply equipment for driving the pump, and the equipment and mechanism for preventing failure due to idle operation or deadline operation of the pump. It is necessary to provide a lot of incidental equipment attached to the pump. Furthermore, if the liquid level in the tank fluctuates due to the swing of the ship, or if the condensed water in the tank is excessively insufficient, the pump will be induced to run idle, or the idle operation prevention equipment will malfunction. Since there is a risk of hindering the stable drive of the water, it is necessary to provide a large-capacity tank as a tank for condensed water. From the above, a large amount of installation space is required to provide the exhaust gas treatment device with equipment for realizing the water supply function.

In the limited space inside a ship, it is required to save the installation space required for installing the exhaust gas treatment device in a marine diesel engine while ensuring the water supply function of the exhaust gas treatment device.

The present invention has been made in view of the above circumstances, and is an exhaust gas treatment device and a water supply capable of saving the installation space of equipment required for the water supply function without deteriorating the water supply function. The purpose is to provide a method.

In order to solve the above-mentioned problems and achieve the object, the exhaust gas treatment apparatus according to the present invention includes a supercharger that pressurizes and compresses the combustion gas and a cooler that cools the combustion gas after pressurizing and compressing. An exhaust gas treatment device applied to a marine diesel engine including an engine body that sweeps air in a cylinder and reciprocates a piston by combustion of fuel using the combustion gas after cooling. The EGR device that cleans the exhaust gas discharged from the vehicle with scrubber water and recirculates the cleaned exhaust gas as a part of the combustion gas, and the condensation generated from the combustion gas after cooling by the cooler. A collection pipe that collects water and the gas pressure of the combustion gas after cooling, a condensed water chamber that stores the condensed water and accumulates the gas pressure through the collecting pipe, the condensed water chamber, and the condensation. A water supply pipe that communicates with a water supply destination device is provided, and the condensed water utilizes the gas pressure accumulated in the condensed water chamber to be supplied from the condensed water chamber through the water supply pipe. It is characterized by being pumped to.

Further, in the above invention, the exhaust gas treatment device according to the present invention includes a supply valve provided in the water supply pipe, a pressure detection unit for detecting the gas pressure, a water level in the condensed water chamber, and an outlet water level in the water supply pipe. When the magnitude relationship between the head differential pressure, which is the pressure corresponding to the head difference between the two, and the gas pressure detected by the pressure detecting unit is determined, and the detected gas pressure is larger than the head differential pressure. The supply valve is controlled to be in an open state, and when the detected gas pressure is equal to or lower than the head differential pressure, the supply valve is controlled to be in a closed state.

Further, in the exhaust gas treatment device according to the present invention, in the above invention, a plurality of the water supply pipes are provided corresponding to the plurality of the supply destination devices so that the head difference with respect to the condensed water chamber is different from each other. The supply valve is provided in each of the plurality of water supply pipes, and the control device is provided with the head differential pressure between the water level of the condensed water chamber and the water supply pipes, and the pressure detection unit. It is characterized in that the open / closed state of a plurality of the supply valves is selectively controlled based on the magnitude relationship with the gas pressure.

Further, in the above invention, the exhaust gas treatment device according to the present invention includes a chamber water level detecting unit for detecting whether or not the water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber, and the control device includes a chamber water level detecting unit. When the detected water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber, the open / closed state of all the supply valves is controlled based on the magnitude relationship between the head differential pressure and the gas pressure. When the detected water level of the condensed water chamber is less than the lower limit water level of the condensed water chamber, all the supply valves are controlled to be closed.

Further, the exhaust gas treatment apparatus according to the present invention has a water treatment tank for recovering and purifying the scrubber water used for cleaning the exhaust gas in the above invention, and the water treatment tank has a water treatment tank. The control device includes a water treatment device that purifies the stored scrubber water and supplies it to the EGR device, and a tank water level detection unit that detects the water level of the water treatment tank. When the water level of the treatment tank is less than the upper limit water level of the water treatment tank, the open / closed state of all the supply valves is controlled based on the magnitude relationship between the head differential pressure and the gas pressure, and the detected state is controlled. When the water level of the water treatment tank is equal to or higher than the upper limit water level of the water treatment tank, all the supply valves are controlled to be closed.

Further, in the exhaust gas treatment device according to the present invention, in the above invention, when the detected water level of the water treatment tank is less than the lower limit water level of the water treatment tank, the control device has a plurality of the supply valves. Among these, at least one of the supply valves, which satisfies the condition that the gas pressure is larger than the head differential pressure, is controlled to be in an open state.

Further, in the exhaust gas treatment device according to the present invention, in the above invention, the gas pressure is the sweep pressure calculated based on the relationship between the sweep pressure of the engine body, the engine load of the engine body and the pressure, or the condensation. It is characterized in that it is the internal pressure of the water chamber or the pressure obtained by correcting the scavenging pressure based on the relationship between the engine load and the pressure of the engine body.

Further, the water supply method according to the present invention uses a supercharger that pressurizes and compresses the combustion gas, a cooler that cools the combustion gas after pressurization and compression, and the combustion gas after cooling. A water supply method applied to a marine diesel engine including an engine body that sweeps air in a cylinder and reciprocates a piston by burning fuel, and is a condensation generated from the combustion gas after cooling by the cooler. The water and the gas pressure of the combustion gas after cooling are collected, and the collected condensed water is stored in the condensed water chamber, and the gas pressure is accumulated in the condensed water chamber and accumulated in the condensed water chamber. It is characterized in that the condensed water is pressure-fed from the condensed water chamber to a supply destination device through a water supply pipe by utilizing the gas pressure.

Further, the water supply method according to the present invention is the pressure corresponding to the head difference between the water level of the condensed water chamber and the outlet water level of the water supply pipe by detecting the gas pressure by the pressure detecting unit in the above invention. The magnitude relationship between the head differential pressure and the gas pressure detected by the pressure detecting unit is determined, and when the detected gas pressure is larger than the head differential pressure, the supply valve of the water supply pipe is opened. When the detected gas pressure is equal to or lower than the head differential pressure, the supply valve of the water supply pipe is controlled to be closed.

Further, in the above invention, the water supply method according to the present invention comprises the water level of the condensed water chamber, the head differential pressure between the plurality of water supply pipes, and the gas pressure detected by the pressure detecting unit. The open / closed state of the plurality of supply valves is selectively controlled based on the magnitude relationship, and the plurality of the water supply pipes correspond to the plurality of the supply destination devices, and the head difference with respect to the condensed water chamber is different from each other. It is provided differently, and the plurality of supply valves are provided in each of the plurality of water supply pipes.

Further, in the water supply method according to the present invention, in the above invention, whether or not the water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber is detected by the chamber water level detecting unit, and the detected condensed water level is detected. When the water level of the water chamber is equal to or higher than the lower limit water level of the condensed water chamber, the open / closed state of all the supply valves is controlled based on the magnitude relationship between the head differential pressure and the gas pressure, and the detected condensed water is detected. When the water level in the chamber is less than the lower limit water level of the condensed water chamber, all the supply valves are controlled to be closed.

Further, in the water supply method according to the present invention, in the above invention, the water level of the water treatment tank for recovering and purifying the scrubber water used for cleaning the exhaust gas from the engine body is determined by the tank water level detection unit. When the water level of the water treatment tank detected by is less than the upper limit water level of the water treatment tank, the open / closed state of all the supply valves based on the magnitude relationship between the head differential pressure and the gas pressure. When the detected water level of the water treatment tank is equal to or higher than the upper limit water level of the water treatment tank, all the supply valves are controlled to be closed.

Further, in the water supply method according to the present invention, when the detected water level of the water treatment tank is less than the lower limit water level of the water treatment tank in the above invention, the gas among the plurality of supply valves. It is characterized in that at least one of the supply valves satisfying the condition that the pressure is larger than the differential pressure of the head is controlled to be in an open state.

Further, in the water supply method according to the present invention, in the above invention, the gas pressure is the sweep pressure calculated based on the relationship between the sweep pressure of the engine body, the engine load of the engine body and the pressure, or the condensation. It is characterized in that it is the internal pressure of the water chamber or the pressure obtained by correcting the scavenging pressure based on the relationship between the engine load and the pressure of the engine body.

According to the present invention, there is an effect that the installation space of the equipment required for the water supply function can be saved without deteriorating the water supply function.

FIG. 1 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the first embodiment of the present invention is applied. FIG. 2 is a flow chart showing an example of the water supply method according to the first embodiment of the present invention. FIG. 3 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the second embodiment of the present invention is applied. FIG. 4 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the third embodiment of the present invention is applied. FIG. 5 is a flow chart showing an example of the water supply method according to the third embodiment of the present invention. FIG. 6 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the fourth embodiment of the present invention is applied. FIG. 7 is a flow chart showing an example of the water supply method according to the fourth embodiment of the present invention.

Hereinafter, preferred embodiments of the exhaust gas treatment apparatus and the water supply method according to the present invention will be described in detail with reference to the accompanying drawings. The present invention is not limited to the present embodiment. In addition, it should be noted that the drawings are schematic, and the relationship between the dimensions of each element, the ratio of each element, and the like may differ from the actual ones. Even between drawings, there may be parts where the relationship and ratio of dimensions are different from each other. Further, in each drawing, the same components are designated by the same reference numerals.

(Embodiment 1)
The exhaust gas treatment apparatus according to the first embodiment of the present invention will be described. FIG. 1 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the first embodiment of the present invention is applied. As shown in FIG. 1, the marine diesel engine 1 includes an engine body 2, a supercharger 3, a cooler 4, a gas-liquid separator 5, a drain pipe 6, an outlet orifice 7, and an exhaust gas treatment device. It is provided with 10. Further, as shown in FIG. 1, the marine diesel engine 1 includes exhaust pipes 101 and 102 as exhaust pipes, air supply equipment or pipes for air supply, air supply units 111 and air supply pipes 112 to 114, and exhaust gas. EGR pipes 121 and 122 as pipes for recirculation are provided. The exhaust gas treatment device 10 is an example of the exhaust gas treatment device according to the first embodiment of the present invention, and as shown in FIG. 1, the EGR device 11, the collection pipe 12, the condensed water chamber 13, and the first water supply pipe 14 A first supply valve 15, a pressure detection unit 16, a chamber water level detection unit 17, a water treatment device 18, a tank water level detection unit 18b, and a control device 19 are provided. Further, as shown in FIG. 1, the water treatment device 18 includes a water treatment tank 18a and circulation pipes 131 and 132.

In FIG. 1, the flow and piping of fluids such as combustion gas and condensed water are appropriately illustrated by solid arrows. The electric signal line is appropriately illustrated by an alternate long and short dash line. This also applies to other drawings.

Although not shown, the engine body 2 is a propulsion engine (main engine) that drives and rotates a propulsion propeller of a ship via a propeller shaft. The engine body 2 is a two-stroke diesel engine such as a uniflow sweep-exhaust type crosshead diesel engine. For example, as shown in FIG. 1, the engine main body 2 includes a plurality of cylinders 2a (four in the first embodiment), a scavenging trunk 2b, and an exhaust manifold 2c. Although not shown, the engine body 2 has an injection device for injecting fuel or the like into the combustion chamber of each cylinder 2a, a control device for driving control of the injection device, and a reciprocating motion (reciprocating motion) along the inside of each cylinder 2a. It is provided with a piston that moves up and down, a crank for rotating the propeller shaft as the piston reciprocates, a crankshaft, a crosshead, and the like.

Each of the plurality of cylinders 2a forms a combustion chamber in which air supply / exhaust for reciprocating the piston, fuel combustion, and the like are performed. The scavenging trunk 2b communicates with the combustion chamber in each cylinder 2a via a scavenging port (not shown) in the engine body 2. The exhaust manifold 2c communicates with the combustion chamber in each cylinder 2a via an exhaust flow path (not shown) in the engine body 2.

The engine body 2 uses the combustion gas after cooling by the cooler 4 to perform scavenging in each cylinder 2a and reciprocating motion of the piston by fuel combustion. Specifically, the engine body 2 reciprocates the piston due to fuel combustion in the combustion chamber in each cylinder 2a, and the rotational motion of the output shaft (specifically, the propeller shaft, the crankshaft, etc.) that outputs the propulsive force of the ship. Convert to. At this time, the engine body 2 is scavenging so that the flow of air supply and exhaust in each cylinder 2a is unidirectional from the lower side to the upper side so as to eliminate the residual exhaust gas. In this scavenging, combustion gas is supplied from the scavenging trunk 2b to the combustion chambers in each cylinder 2a, and the exhaust gas after combustion is discharged from the combustion chambers in each cylinder 2a to the exhaust manifold 2c. In such an engine body 2, as shown in FIG. 1, an air supply pipe 114 is connected to the scavenging trunk 2b, and an exhaust pipe 101 is connected to the exhaust manifold 2c. The exhaust gas is a gas discharged from the engine body 2 to the outside through the exhaust pipe 101 or the like. Hereinafter, the exhaust gas means the exhaust gas discharged from the engine body 2.

The supercharger 3 uses the exhaust gas from the engine body 2 to pressurize and compress the combustion gas supplied to the engine body 2. As shown in FIG. 1, the supercharger 3 includes a compressor 3a, a turbine 3b, and a rotating shaft 3c. The compressor 3a and the turbine 3b are each composed of an impeller or the like, and are connected to each other by a rotating shaft 3c so as to rotate integrally with the rotating shaft 3c as a central axis. Further, on the gas inlet side of the compressor 3a, an air supply unit 111 for sucking gas such as new air (also referred to as fresh air) from the outside (atmosphere) is provided. The outlet end of the EGR pipe 122 is connected to the vicinity of the air supply unit 111. As a result, the gas inlet side of the compressor 3a is configured so that the air from the air supply unit 111 and the recirculated gas from the EGR pipe 122 can be mixed and supplied. An air supply pipe 112 leading to the cooler 4 is connected to the gas outlet side of the compressor 3a. An exhaust pipe 101 leading to the exhaust manifold 2c of the engine body 2 is connected to the gas inlet side of the turbine 3b. An exhaust pipe 102 leading to a chimney (not shown) or the like that discharges exhaust gas to the outside is connected to the gas outlet side of the turbine 3b.

In the supercharger 3 having such a configuration, the turbine 3b receives the exhaust gas discharged from the exhaust manifold 2c of the engine main body 2 through the exhaust pipe 101. The turbine 3b rotates with energy such as the pressure of the exhaust gas received, and discharges the exhaust gas used for this rotation to the exhaust pipe 102. The rotation of the turbine 3b is transmitted to the compressor 3a by the rotation shaft 3c. As a result, the compressor 3a rotates with the rotation of the turbine 3b to suck in the combustion gas, and pressurizes and compresses the sucked combustion gas. The combustion gas is a mixed gas of air from the air supply unit 111 and recirculation gas from the EGR pipe 122 when the EGR device 11 is in operation, and is a mixed gas when the EGR device 11 is stopped. , Only the air from the air supply unit 111. The combustion gas after pressurization and compression by the compressor 3a is supplied to the cooler 4 through the air supply pipe 112.

The cooler 4 is for cooling the combustion gas after pressurization and compression by the supercharger 3 (specifically, the compressor 3a). As shown in FIG. 1, the outlet end of the air supply pipe 112 leading to the compressor 3a is connected to the gas inlet side of the cooler 4. The inlet end of the air supply pipe 113 leading to the gas-liquid separation device 5 is connected to the gas outlet side of the cooler 4. The cooler 4 cools the combustion gas that has been pressurized and compressed by the compressor 3a to a high temperature and high pressure state by, for example, heat exchange with cooling water. Hereinafter, the term "combustion gas after cooling" means a combustion gas in a high pressure state which is pressurized and compressed by the compressor 3a and cooled by the cooler 4 unless otherwise specified.

The gas-liquid separation device 5 is a device for separating combustion gas and droplets (condensed water) after cooling by the cooler 4. As shown in FIG. 1, the outlet end of the air supply pipe 113 leading to the cooler 4 is connected to the gas inlet side of the gas-liquid separation device 5. The inlet end of the air supply pipe 114 leading to the scavenging trunk 2b of the engine body 2 is connected to the gas outlet side of the gas-liquid separation device 5. When the gas-liquid separation device 5 generates condensed water in the combustion gas after cooling by the cooler 4, the gas-liquid separation device 5 captures the condensed water, separates it from the combustion gas, and removes it.

The combustion gas from which the condensed water has been removed by the gas-liquid separator 5 has a high gas pressure boosted by the pressurizing and compressing action of the compressor 3a described above, and the engine is passed through the air supply pipe 114 from the gas-liquid separator 5. Air is supplied to the scavenging trunk 2b of the main body 2. As described above, the combustion gas supplied to the scavenging trunk 2b is used for scavenging the inside of each cylinder 2a of the engine body 2. That is, the gas pressure of this combustion gas is the sweep pressure of the engine body 2.

On the other hand, in the exhaust gas treatment device 10, the EGR device 11 cleans the exhaust gas discharged from the engine body 2 with scrubber water, and recirculates the washed exhaust gas as a part of the above-mentioned combustion gas. .. The EGR device 11 reduces the content of NOx in the exhaust gas by such recirculation of the exhaust gas. In the first embodiment, as shown in FIG. 1, the EGR device 11 includes a scrubber 11a, a demista 11b, an EGR blower 11c, a recovery tank 11d, a recovery pipe 11e, and a pump 11f, and is a marine diesel engine. It is mounted on 1.

The scrubber 11a cleans a part of the exhaust gas discharged from the engine body 2 so that it can be used as a recirculation gas. In the first embodiment, the scrubber 11a is, for example, a Venturi-type scrubber provided with an injection nozzle or the like for injecting scrubber water or the like. Further, as shown in FIG. 1, the outlet end of the EGR pipe 121 is connected to the gas inlet side of the scrubber 11a. The inlet end of the EGR pipe 121 is connected to the middle part of the exhaust pipe 102 described above. Each outlet end of the first water supply pipe 14 and the circulation pipe 132, which will be described later, is connected to the water inlet side of the scrubber 11a. On the other hand, the lower part of the scrubber 11a communicates with the demista 11b.

In the first embodiment, the scrubber 11a receives a part of the exhaust gas from the engine body 2 through the EGR pipe 121, and injects the scrubber water into the received exhaust gas. For example, the scrubber 11a uses the water supplied through the circulation pipe 132 (the scrubber water after the treatment by the water treatment device 18) as the scrubber water for cleaning the exhaust gas. Further, the condensed water supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14 is used for cleaning the scrubber 11a itself (for example, an injection nozzle, a filter, etc.). The scrubber 11a cleans the exhaust gas by removing fine particles such as soot and harmful substances such as SOx from the exhaust gas by injecting the scrubber water onto the exhaust gas. The exhaust gas after cleaning flows into the demista 11b together with the scrubber water after use as a recirculation gas.

The demista 11b is a facility for separating the recirculated gas from the scrubber 11a and the scrubber water. The demista 11b is composed of, for example, a hollow structure. As shown in FIG. 1, the outlet portion of the scrubber 11a described above is connected to the demister 11b. The inlet end of the recovery pipe 11e leading to the recovery tank 11d is connected to the lower part of the demista 11b (the bottom in the first embodiment). The demista 11b separates the gas-liquid mixed fluid of the recirculated gas after cleaning and the scrubber water after use that has flowed from the scrubber 11a into a gas and a liquid. Of these separated recirculation gas and scrubber water, the recirculation gas is sucked by the EGR blower 11c from the gas discharge port of the demista 11b and sent to the compressor 3a through the EGR pipe 122. The scrubber water is led out from the lower part of the demista 11b to the recovery tank 11d through the recovery pipe 11e.

The EGR blower 11c is a blower for sucking in the recirculated gas produced by the scrubber 11a as a part of the combustion gas and sending it out. As shown in FIG. 1, the EGR blower 11c is provided, for example, on the upper part of the demister 11b. Further, the inlet end of the EGR pipe 122 is connected to the gas outlet side of the EGR blower 11c. The EGR blower 11c sucks the recirculated gas separated from the scrubber water by the demista 11b from the inside of the demista 11b and pumps it to the EGR pipe 122. Such a recirculating gas merges with the air from the air supply unit 111 through the EGR pipe 122 and is used as a part of the above-mentioned combustion gas.

The recovery tank 11d is a tank for recovering the scrubber water used for cleaning the exhaust gas. As shown in FIG. 1, the recovery tank 11d is arranged below the demister 11b in the EGR device 11 and communicates with the demister 11b via the recovery pipe 11e. The recovery tank 11d recovers the scrubber water (scrubber water Wb in FIG. 1) used for cleaning the exhaust gas in the scrubber 11a from the demista 11b through the recovery pipe 11e. The recovery tank 11d stores the scrubber water Wb thus recovered. As a result, the recovery tank 11d can appropriately prepare the scrubber water Wb before the purification treatment, which is the source of the scrubber water circulated between the scrubber 11a and the water treatment device 18.

The pump 11f is for supplying the scrubber water Wb used for cleaning the exhaust gas to the water treatment device 18. As shown in FIG. 1, the inlet side of the pump 11f is provided at the outlet portion of the recovery tank 11d. The inlet end of the circulation pipe 131 leading to the water treatment device 18 is connected to the outlet side of the pump 11f. The pump 11f sucks the scrubber water Wb from the recovery tank 11d, and pumps the sucked scrubber water Wb to the water treatment device 18 through the circulation pipe 131. The scrubber water Wb supplied to the water treatment apparatus 18 is purified by the water treatment apparatus 18, and then supplied again from the water treatment apparatus 18 to the scrubber 11a through the circulation pipe 132.

Although not particularly shown, the operation of the EGR device 11 (specifically, each drive of the EGR blower 11c and the pump 11f, etc.) is controlled by a predetermined control device. This control device operates the EGR device 11 when the load of the engine body 2 (hereinafter referred to as an engine load) is equal to or higher than a predetermined reference value. Further, this control device stops the operation of the EGR device 11 when the engine load is less than the reference value. However, since the engine load below the reference value may rise again, only the circulation of the recirculated gas by the EGR device 11 may be stopped, and the operation of the water treatment device 18 and the circulation of the scrubber water may be continued. It is possible. Here, the international exhaust gas regulations for marine diesel engines require that NOx be reduced by EGR when the engine load is 25% or more. Therefore, in the present invention, based on this exhaust gas regulation, in order to surely reduce NOx by EGR when the engine load is 25% or more, the reference value of the engine load is a value of 25% or less, for example, 20%. Is set to.

The collection pipe 12 is a pipe that collects the condensed water generated from the combustion gas after cooling by the cooler 4 and the gas pressure of the combustion gas after cooling by the cooler 4. As shown in FIG. 1, the collection pipe 12 includes a first collection pipe 12a that collects condensed water from the cooler 4, and a second collection pipe 12b that collects condensed water from the gas-liquid separation device 5. In the first collection pipe 12a, the inlet end is connected to the drain port of the cooler 4 and the outlet end is connected to the inlet portion of the condensed water chamber 13 to communicate the inside of the cooler 4 and the inside of the condensed water chamber 13. It is provided as follows. The drain port of the cooler 4 is formed at the bottom of the cooler 4, for example. In the second collection pipe 12b, the inlet end is connected to the drain port of the gas-liquid separation device 5 and the outlet end is connected to the middle part of the first collection pipe 12a, and the gas-liquid separation device 5 is connected via the first collection pipe 12a. It is provided so as to communicate the inside of the water chamber 13 with the inside of the condensed water chamber 13. The drain port of the gas-liquid separation device 5 is formed at the bottom of the gas-liquid separation device 5, for example.

In the first embodiment, the high-temperature and high-pressure combustion gas after pressure compression by the compressor 3a is cooled inside the cooler 4, and condensed water is generated from the cooled combustion gas. A part of the condensed water generated in this way is accumulated inside the cooler 4, and the rest is supplied to the gas-liquid separation device 5 through the air supply pipe 113 together with the combustion gas after cooling. The first collection pipe 12a collects the condensed water accumulated inside the cooler 4 from the cooler 4 together with a part of the combustion gas after cooling. The second collection pipe 12b collects the condensed water separated from the cooled combustion gas by the gas-liquid separator 5 from the gas-liquid separator 5 together with a part of the cooled combustion gas. The collection pipe 12 including the first collection pipe 12a and the second collection pipe 12b collects condensed water from each of the cooler 4 and the gas-liquid separation device 5 together with a part of the combustion gas after cooling. .. In this way, the collection pipe 12 collects the gas pressure of the combustion gas after cooling and the condensed water. The collected condensed water is guided to the condensed water chamber 13 together with a part of the combustion gas after cooling by the collecting pipe 12.

The condensed water chamber 13 is a pressure vessel that stores the above-mentioned condensed water and stores the pressure for pumping the stored condensed water to the supply destination device. As shown in FIG. 1, the condensed water chamber 13 is arranged below the cooler 4 and the gas-liquid separator 5, and communicates with each of the cooler 4 and the gas-liquid separator 5 via a collection pipe 12. ing. The above-mentioned condensed water flows into the condensed water chamber 13 from each of the cooler 4 and the gas-liquid separation device 5 through the collection pipe 12 together with a part of the combustion gas after cooling. The condensed water chamber 13 stores the inflowing condensed water (condensed water Wa shown in FIG. 1) through the collection pipe 12 and accumulates the gas pressure of the inflowing combustion gas.

Further, as shown in FIG. 1, a drain pipe 6 is connected to the upper part of the condensed water chamber 13. The drain pipe 6 discharges the excess amount of the condensed water stored in the condensed water chamber 13 exceeding the upper limit water level of the condensed water chamber 13 from the condensed water chamber 13. For example, the drain pipe 6 is provided in the marine diesel engine 1 so that the outlet end faces downward, and the excess of the condensed water is discharged from the condensed water chamber 13 to the lower side of the marine diesel engine 1. On the other hand, as shown in FIG. 1, an outlet orifice 7 is provided in a portion near the lower end of the drain pipe 6. The outlet orifice 7 narrows the outlet portion of the drain pipe 6 and prevents an excessive decrease in the gas pressure accumulated in the condensed water chamber 13 while ensuring the drainage function of the drain pipe 6.

Here, in the first embodiment, as shown in FIG. 1, the condensed water chamber 13, the cooler 4, and the gas-liquid separation device 5 communicate with each other via the collection pipe 12. Further, the compressor 3a of the supercharger 3 and the cooler 4 communicate with each other via the air supply pipe 112, and the cooler 4 and the gas-liquid separator 5 communicate with each other via the air supply pipe 113, so that the gas-liquid separator 5 And the scavenging trunk 2b of the engine body 2 communicate with each other via the air supply pipe 114. In such a structure, the gas pressure accumulated in the condensed water chamber 13 becomes the gas pressure of the combustion gas flowing inside each of the cooler 4, the gas-liquid separator 5, the collection pipe 12, and the air supply pipes 112 to 114. Equivalent to. Further, the gas pressure of the combustion gas in each of these interiors corresponds to the gas pressure of the combustion gas supplied to the scavenging trunk 2b. That is, in the first embodiment, the gas pressure accumulated in the condensed water chamber 13 corresponds to the sweep pressure P of the engine body 2. Further, the gas pressure of the combustion gas in the scavenging trunk 2b is a gas pressure obtained by pressurizing and compressing the combustion gas by the compressor 3a of the supercharger 3 driven by using the exhaust gas. Therefore, the sweep pressure P of the engine body 2 increases as the engine load increases, and decreases as the engine load decreases. The outlet orifice 7 described above can suppress a decrease in the sweep pressure P of the engine body 2 by preventing an excessive decrease in the gas pressure in the condensed water chamber 13.

The first water supply pipe 14 is an example of a water supply pipe for supplying the condensed water Wa stored in the condensed water chamber 13 to the supply destination device. As shown in FIG. 1, the first water supply pipe 14 is arranged so as to communicate the condensed water chamber 13 and the scrubber 11a which is an example of the supply destination device. Specifically, the first water supply pipe 14 has an inlet end connected to a predetermined portion of the condensed water chamber 13 and an outlet end connected to a water supply port of the scrubber 11a, and a head difference between the condensed water chamber 13 and the scrubber 11a. It is arranged so that h1 occurs. In the first embodiment, for example, as shown in FIG. 1, a predetermined portion of the condensed water chamber 13 to which the inlet end of the first water supply pipe 14 is connected is a side wall portion near the bottom of the condensed water chamber 13. The water supply port to which the outlet end of the first water supply pipe 14 of the scrubber 11a is connected is formed on the side wall portion near the upper end of the scrubber 11a. The condensed water Wa is pressure-fed from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14 by utilizing the gas pressure accumulated in the condensed water chamber 13. As a result, the condensed water Wa is supplied to the scrubber 11a at a pressure that can be injected.

In the present invention, the head difference is defined as the height difference between the head of the condensed water chamber 13 which is the supply source device of the condensed water Wa and the head of the device to which the condensed water Wa is supplied. That is, in the first embodiment, as shown in FIG. 1, the head difference h1 between the condensed water chamber 13 and the scrubber 11a is the height difference between the water level of the condensed water chamber 13 and the outlet water level of the first water supply pipe 14. .. For example, the water level of the condensed water chamber 13 is a position in the height direction of the liquid level Sa of the condensed water Wa stored in the condensed water chamber 13. The outlet water level of the first water supply pipe 14 is a position in the height direction of the upper end of the inner wall at the outlet portion (water supply port of the scrubber 11a) of the first water supply pipe 14. The reference positions of the water level of the condensed water chamber 13 and the outlet water level of the first water supply pipe 14 are the same as each other, for example, the bottom surface of the condensed water chamber 13.

Further, the head difference h1 is set so that the condensed water Wa can be pumped from the condensed water chamber 13 to the scrubber 11a by utilizing the gas pressure in the condensed water chamber 13 during a desired period. For example, when the supply destination device is the scrubber 11a of the EGR device 11, the head difference h1 is set so that the condensed water Wa can be pumped to the scrubber 11a during the operation of the EGR device 11. In the first embodiment, the EGR device 11 operates when the engine load is equal to or higher than the above-mentioned reference value. That is, the minimum value of the engine load during operation of the EGR device 11 is the reference value (for example, 20%). Further, the gas pressure in the condensed water chamber 13 corresponds to the gas pressure of the combustion gas supplied to the scavenging trunk 2b (that is, the scavenging pressure P of the engine body 2) as described above. Therefore, the head difference h1 is the height difference between the head of the lower supply source device and the head of the higher supply destination device that can pump water using the sweep pressure P when the engine load is the reference value. It is set to the following (for example, 3 m or less).

The first supply valve 15 is an example of a supply valve that opens or closes a water supply pipe for pumping condensed water Wa to a supply destination device. In the first embodiment, as shown in FIG. 1, the first supply valve 15 is provided in the middle of the first water supply pipe 14. The first supply valve 15 is driven to open and close under the control of the control device 19, thereby opening or closing the first water supply pipe 14.

The pressure detection unit 16 detects the gas pressure used for pumping the condensed water Wa to the supply destination device. For example, as shown in FIG. 1, the pressure detection unit 16 is provided in the scavenging trunk 2b of the engine body 2. In the first embodiment, the pressure detecting unit 16 uses the gas pressure in the scavenging trunk 2b corresponding to the gas pressure in the condensed water chamber 13 as the gas pressure used for pumping the condensed water Wa to the scrubber 11a, that is, the gas pressure in the scavenging trunk 2b. The sweep pressure P of the engine body 2 is detected. Each time, the pressure detection unit 16 transmits an electric signal indicating the detected gas pressure (sweeping pressure P) to the control device 19.

The chamber water level detection unit 17 is an example of a water level detection unit that detects the water level of the condensed water chamber 13. For example, as shown in FIG. 1, the chamber water level detection unit 17 is provided in the condensed water chamber 13 and has a detector at a position of a lower limit water level La preset in the condensed water chamber 13. The lower limit water level La of the condensed water chamber 13 is higher than the position of the upper end of the inner wall at the inlet portion of the first water supply pipe 14 or higher than the position from the viewpoint that the condensed water Wa can be stably pumped through the first water supply pipe 14. It is preferable to set to. In the first embodiment, the chamber water level detection unit 17 detects whether or not the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La of the condensed water chamber 13. Specifically, the chamber water level detection unit 17 detects whether or not the liquid level Sa of the condensed water Wa in the condensed water chamber 13 is located at a higher level than the lower limit water level La. Each time, the chamber water level detection unit 17 transmits an electric signal indicating the water level detection result of the condensed water chamber 13 to the control device 19.

The water treatment device 18 is an example of a device that recovers the scrubber water used for cleaning the exhaust gas from the EGR device 11 for purification treatment, and supplies the purified scrubber water to the EGR device 11. In the first embodiment, as shown in FIG. 1, the water treatment device 18 includes a water treatment tank 18a and circulation pipes 131 and 132, and is provided outside the marine diesel engine 1. The water treatment tank 18a is a tank used for recovering and purifying the scrubber water used for cleaning the exhaust gas. The circulation pipes 131 and 132 are pipes for circulating scrubber water between the EGR device 11 and the water treatment device 18. The water treatment device 18 receives the used scrubber water Wb from the recovery tank 11d of the EGR device 11 through the circulation pipe 131. The water treatment apparatus 18 collects and stores the received scrubber water Wb in the water treatment tank 18a, and purifies the scrubber water Wb stored in the water treatment tank 18a to purify the scrubber after the purification treatment. Obtain water Wc. FIG. 1 shows a water treatment tank 18a in a state in which the scrubber water Wc after the purification treatment is stored. The water treatment device 18 pumps and supplies the scrubber water Wc from the water treatment tank 18a to the scrubber 11a through the circulation pipe 132 by the action of a pump (not shown).

Further, as shown in FIG. 1, the water treatment tank 18a of the water treatment device 18 is provided with a tank water level detection unit 18b. The tank water level detection unit 18b is an example of a water level detection unit that detects the water level of the water treatment tank 18a. For example, as shown in FIG. 1, the tank water level detection unit 18b has detectors at each position of the upper limit water level Hb and the lower limit water level Lb preset in the water treatment tank 18a. In the first embodiment, the tank water level detection unit 18b has any of the water level of the water treatment tank 18a of the upper limit water level Hb or more, the lower limit water level Lb or more and the upper limit water level Hb or less, or the lower limit water level Lb or less of the water treatment tank 18a. Is detected. Specifically, in the tank water level detection unit 18b, the liquid level Sb of the scrubber water (scrubber water Wc in FIG. 1) in the water treatment tank 18a is the upper limit water level Hb or more, the lower limit water level Lb or more and less than the upper limit water level Hb, the lower limit. Detects where the water level is below Lb. Each time, the tank water level detection unit 18b transmits an electric signal indicating the water level detection result of the water treatment tank 18a to the control device 19.

The control device 19 is an example of a device that controls the execution and stop of the water supply of the exhaust gas treatment device 10. In the first embodiment, the control device 19 controls the opening / closing drive of the first supply valve 15 provided in the first water supply pipe 14 that communicates the condensed water chamber 13 and the scrubber 11a. Specifically, the control device 19 is composed of a CPU, a memory, a sequencer, and the like for executing various programs. The control device 19 receives an electric signal from the pressure detection unit 16, the chamber water level detection unit 17, the tank water level detection unit 18b, and the like, and based on the received electric signal and the engine load of the engine body 2, the first supply valve 15 Controls open / close drive.

For example, the control device 19 determines the magnitude relationship between the head differential pressure P (h1) between the condensed water chamber 13 and the scrubber 11a and the gas pressure (for example, sweep pressure P) detected by the pressure detecting unit 16. When the detected gas pressure is larger than the head differential pressure P (h1), the control device 19 controls the first supply valve 15 to be in the open state, and the detected gas pressure is equal to or less than the head differential pressure P (h1). If, the first supply valve 15 is controlled to be in the closed state.

Here, the head difference h1 is such that the water level of the condensed water chamber 13 (the position of the condensed water Wa in the height direction of the liquid level Sa) changes according to the balance between the storage and pumping of the condensed water Wa. It increases or decreases as it changes. For example, the head difference h1 increases as the liquid level Sa of the condensed water Wa decreases toward the lower limit water level La of the condensed water chamber 13, and the liquid level Sa of the condensed water Wa becomes the lower limit water level La of the condensed water chamber 13. Maximum value when located. In the first embodiment, the above maximum value is used as an example of the head difference h1. That is, the head differential pressure P (h1) is a pressure corresponding to the maximum value within a predetermined range of the head difference h1 that can be taken between the condensed water chamber 13 and the scrubber 11a. Alternatively, the chamber water level detection unit 17 is configured to continuously or intermittently detect the water level of the condensed water chamber 13 at predetermined time intervals, and the head differential pressure P (h1) is detected by the chamber water level detection unit 17. The pressure may be a pressure corresponding to the head difference h1 between the water level of the condensed water chamber 13 and the outlet water level of the first water supply pipe 14.

Further, in the control device 19, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is equal to or higher than the lower limit water level La of the condensed water chamber 13, all the supply valves (the first supply valve in the first embodiment). Regarding 15), the open / closed state is controlled based on the magnitude relationship between the above-mentioned head differential pressure P (h1) and the detected gas pressure. On the other hand, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is less than the lower limit water level La of the condensed water chamber 13, the control device 19 closes all the supply valves (first supply valve 15). To control.

Further, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is less than the upper limit water level Hb of the water treatment tank 18a, the control device 19 applies to all the supply valves (first supply valve 15). The open / closed state is controlled based on the magnitude relationship between the head differential pressure P (h1) described above and the detected gas pressure. On the other hand, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is equal to or higher than the upper limit water level Hb of the water treatment tank 18a, the control device 19 closes all the supply valves (first supply valve 15). Control to closed state.

Further, the control device 19 describes all the supply valves (first supply valve 15) when the engine load of the engine body 2 is equal to or higher than the above-mentioned reference value, that is, when the EGR device 11 is in operation. The open / closed state is controlled based on the magnitude relationship between the head differential pressure P (h1) and the detected gas pressure. On the other hand, the control device 19 closes all the supply valves (first supply valve 15) when the engine load of the engine body 2 is less than the above-mentioned reference value, that is, when the EGR device 11 is stopped. To control.

Next, the water supply method according to the first embodiment of the present invention will be described. FIG. 2 is a flow chart showing an example of the water supply method according to the first embodiment of the present invention. The water supply method according to the first embodiment is a water supply method applied to a marine diesel engine 1 including a supercharger 3, a cooler 4, and an engine body 2 as shown in FIG. In this water supply method, the exhaust gas treatment device 10 described above appropriately performs each of the treatments of steps S101 to S108 illustrated in FIG. 2, thereby utilizing the accumulated pressure in the condensed water chamber 13 as an example of the supply destination device. Supply or stop the supply of condensed water Wa to a certain scrubber 11a.

Specifically, in the water supply method according to the first embodiment, the exhaust gas treatment device 10 collects condensed water under the scavenging pressure of the engine body 2 as shown in FIG. 2 (step S101). In step S101, the collection pipe 12 collects the condensed water generated from the combustion gas after cooling by the cooler 4 and the gas pressure of the combustion gas after cooling.

Specifically, the collection pipe 12 collects the condensed water collected inside the cooler 4 together with a part of the combustion gas after cooling from the cooler 4, and collects the collected condensed water and the combustion gas in the cooler. Lead from 4 to the condensed water chamber 13. In parallel with this, the collection pipe 12 collects and collects the condensed water separated from the combustion gas after cooling by the gas-liquid separation device 5 from the gas-liquid separation device 5 together with a part of the combustion gas after cooling. The condensed water and the combustion gas are guided from the gas-liquid separator 5 to the condensed water chamber 13. In the first embodiment, the gas pressure of the combustion gas after cooling corresponds to the sweep pressure P of the engine body 2. That is, in step S101, the collection pipe 12 collects and condenses the condensed water in a state in which a part of the combustion gas having the gas pressure of the sweep pressure P is mixed from each of the cooler 4 and the gas-liquid separation device 5. It leads to the water chamber 13.

After executing the above-mentioned step S101, the exhaust gas treatment device 10 stores the condensed water together with the sweep pressure P (step S102). In step S102, the exhaust gas treatment device 10 stores the condensed water collected by the collection pipe 12 in the condensed water chamber 13, and accumulates the gas pressure of the combustion gas collected together with the condensed water in the condensed water chamber 13. Specifically, the condensed water chamber 13 receives the condensed water generated from the cooled combustion gas from the cooler 4 through the collecting pipe 12 together with a part of the cooled combustion gas. In addition to this, the condensed water chamber 13 receives the condensed water separated from the cooled combustion gas from the gas-liquid separation device 5 through the collecting pipe 12 together with a part of the cooled combustion gas. The condensed water chamber 13 stores the condensed water received in this way, and also accumulates the gas pressure of the cooling gas mixed with the condensed water. In the first embodiment, as shown in FIG. 1, the condensed water chamber 13 stores the condensed water Wa in a state where the accumulated gas pressure is applied (see the thick line arrow in FIG. 1).

After executing the above-mentioned step S102, the exhaust gas treatment device 10 determines whether or not the EGR device 11 is in operation (step S103). In step S103, the control device 19 determines whether or not the EGR device 11 is in operation based on the engine load of the engine body 2.

For example, in the first embodiment, the EGR device 11 operates when the engine load is equal to or higher than the above-mentioned reference value based on the exhaust gas regulation, and stops when the engine load is less than the above-mentioned reference value. Based on this, the control device 19 determines that the EGR device 11 is in operation when the engine load is equal to or higher than the above reference value, and the EGR device 11 is stopped when the engine load is less than the above reference value. Judge that. The engine load can be calculated based on, for example, the engine speed per unit time of the engine body 2 and the fuel injection amount in one cycle. Even if the control device 19 acquires the engine speed and the fuel injection amount from the control device or the sensor (neither shown) of the engine body 2, and derives the engine load based on the acquired information. Alternatively, the engine load may be acquired from the control device of the engine body 2.

When it is determined in step S103 described above that the EGR device 11 is in operation (step S103, Yes), in the exhaust gas treatment device 10, whether the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La of the condensed water chamber 13. It is determined whether or not (step S104).

In step S104, the exhaust gas treatment device 10 detects whether or not the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La by the chamber water level detecting unit 17. The chamber water level detection unit 17 transmits an electric signal indicating the detection result of the water level of the condensed water chamber 13 to the control device 19. The control device 19 receives an electric signal from the chamber water level detection unit 17, and based on the detection result of the water level of the condensed water chamber 13 indicated by the received electric signal, the water level of the condensed water chamber 13 is the lower limit water level La. Judge whether or not it is the above.

Specifically, when the control device 19 receives an electric signal from the chamber water level detection unit 17 indicating a detection result that the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La, the water level of the condensed water chamber 13 is the lower limit water level. It is judged that it is La or more. Further, when the control device 19 receives an electric signal from the chamber water level detection unit 17 indicating a detection result that the water level of the condensed water chamber 13 is lower than the lower limit water level La, the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La. It is judged that there is no water level (less than the lower limit water level La).

When it is determined in step S104 described above that the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La (Step S104, Yes), the exhaust gas treatment device 10 has the water level of the water treatment tank 18a of the water treatment tank 18a. It is determined whether or not the upper limit water level is less than Hb (step S105).

In step S105, the exhaust gas treatment device 10 detects whether or not the water level of the water treatment tank 18a is less than the upper limit water level Hb by the tank water level detection unit 18b. The tank water level detection unit 18b transmits an electric signal indicating the detection result of the water level of the water treatment tank 18a to the control device 19. The control device 19 receives an electric signal from the tank water level detection unit 18b, and based on the detection result of the water level of the water treatment tank 18a indicated by the received electric signal, the water level of the water treatment tank 18a is the upper limit. Determine if the water level is below Hb.

Specifically, when the control device 19 receives an electric signal from the tank water level detection unit 18b indicating a detection result that the water level of the water treatment tank 18a is less than the upper limit water level Hb, the water level of the water treatment tank 18a is raised. It is judged that the upper limit water level is less than Hb. Further, when the control device 19 receives an electric signal from the tank water level detection unit 18b indicating a detection result that the water level of the water treatment tank 18a is equal to or higher than the upper limit water level Hb, the water level of the water treatment tank 18a becomes the upper limit water level Hb. It is judged that it is not less than (the upper limit water level is Hb or more).

When it is determined in step S105 described above that the water level of the water treatment tank 18a is less than the upper limit water level Hb (steps S105, Yes), the exhaust gas treatment device 10 has the gas pressure and head accumulated in the condensed water chamber 13. The magnitude relationship with the differential pressure P (h1) is determined (step S106). The head differential pressure P (h1) is a pressure corresponding to the head difference h1 (see FIG. 1) between the water level of the condensed water chamber 13 and the outlet water level of the first water supply pipe 14.

In step S106, the exhaust gas treatment device 10 detects the gas pressure applied to the condensed water Wa in the condensed water chamber 13 by the pressure detecting unit 16. The pressure detection unit 16 detects, for example, the gas pressure of the combustion gas in the scavenging trunk 2b (that is, the scavenging pressure P of the engine body 2) as the gas pressure, and controls an electric signal indicating the detected scavenging pressure P. It is transmitted to the device 19. The control device 19 receives an electric signal from the pressure detecting unit 16 and compares the detected pressure (sweeping pressure P in the present embodiment 1) indicated by the received electric signal with the head differential pressure P (h1). As a result, the control device 19 determines the magnitude relationship between the sweep pressure P and the head differential pressure P (h1).

In step S106 described above, when the control device 19 determines that the detected sweep pressure P is larger than the head differential pressure P (h1) (step S106, Yes), the exhaust gas treatment device 10 is the first supply valve 15. Is opened and the condensed water Wa is pumped to the supply destination device (step S107). In step S107, the control device 19 controls the first supply valve 15 in the open state. The first supply valve 15 is opened and driven based on the control of the control device 19, thereby opening the first water supply pipe 14. As a result, the exhaust gas treatment device 10 pumps and supplies the condensed water Wa from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14 by utilizing the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13. To do.

On the other hand, in step S106 described above, when the control device 19 determines that the detected sweep pressure P is equal to or less than the head differential pressure P (h1) (steps S106, No), the exhaust gas treatment device 10 is the first supply valve. 15 is closed (step S108). In step S108, the control device 19 controls the first supply valve 15 in the closed state. The first supply valve 15 is closed and driven under the control of the control device 19, thereby closing the first water supply pipe 14. As a result, the exhaust gas treatment device 10 stops the pumping supply of the condensed water Wa from the condensed water chamber 13 to the scrubber 11a.

After executing the above-mentioned step S107 or step S108, the exhaust gas treatment device 10 returns to the above-mentioned step S101 and repeats the processing after this step S101. If it is determined in step S103 described above that the EGR device 11 is not in operation (steps S103, No), the exhaust gas treatment device 10 proceeds to step S108 described above, and repeats the processes after step S108. Further, when it is determined in step S104 described above that the water level of the condensed water chamber 13 is not equal to or higher than the lower limit water level La (steps S104, No), the exhaust gas treatment device 10 proceeds to step S108 described above, and the steps S108 and subsequent steps S108 and thereafter. Repeat the process. If it is determined in step S105 above that the water level in the water treatment tank 18a is not less than the upper limit water level Hb (steps S105, No), the exhaust gas treatment apparatus 10 proceeds to step S108 described above, and the steps S108 and thereafter. Repeat the process of.

As described above, in the exhaust gas treatment device 10 and the water supply method according to the first embodiment of the present invention, the combustion gas (combustion after cooling) that has been pressurized and compressed by the supercharger 3 and cooled by the cooler 4. The condensed water generated from the gas) and the gas pressure of the combustion gas after cooling are collected by the collecting pipe 12, the collected condensed water is stored in the condensed water chamber 13, and this gas pressure is stored in the condensed water chamber. The gas pressure accumulated in the condensed water chamber 13 is used to pump the condensed water Wa from the condensed water chamber 13 to the scrubber 11a, which is an example of the supply destination device, through the first water supply pipe 14.

With the above configuration, the gas pressure of the existing combustion gas in the marine diesel engine 1 is condensed without installing the pump and its ancillary equipment, which were conventionally required when supplying water from the tank to the supply destination device through the pipe. By effectively utilizing the pumping of water Wa, the condensed water Wa can be supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14. Therefore, the space required for installing the pump and its ancillary equipment can be omitted, and the conventional tank as a storage container for the condensed water Wa can be replaced with a smaller condensed water chamber 13. As a result, it is possible to save the installation space of equipment such as chambers and pipes required for this water supply function without deteriorating the water supply function to the scrubber 11a.

In addition to this, since the supply destination device that is the pumping supply destination of the condensed water Wa is the scrubber 11a, the condensed water Wa that is cleaner than the scrubber water is pumped and supplied to the scrubber 11a, and the scrubber 11a itself (for example, an injection nozzle or a filter) is supplied. Etc.) can be washed.

Further, in the exhaust gas treatment device 10 and the water supply method according to the first embodiment of the present invention, the gas pressure used for pumping the condensed water Wa is detected by the pressure detecting unit 16 and between the condensed water chamber 13 and the scrubber 11a. The magnitude relationship between the head differential pressure P (h1) and the gas pressure detected by the pressure detection unit 16 is determined, and the detected gas pressure (for example, sweep pressure P) is larger than the head differential pressure P (h1). In this case, the first supply valve 15 of the first water supply pipe 14 is controlled to be open, and when the detected gas pressure is equal to or less than the head differential pressure P (h1), the first supply valve 15 of the first water supply pipe 14 is pressed. It is controlled to the closed state.

With the above configuration, the condensed water chamber 13 and the scrubber 11a are communicated with each other via the first water supply pipe 14 only when the condensed water Wa can be pumped and supplied to the scrubber 11a by using the gas pressure accumulated in the condensed water chamber 13. Can be made to. As a result, the condensed water Wa can be stably pumped and supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14, and the backflow of the scrubber water and the exhaust gas from the scrubber 11a to the condensed water chamber 13 is prevented. be able to.

Further, in the exhaust gas treatment device 10 and the water supply method according to the first embodiment of the present invention, the water level of the condensed water chamber 13 is detected by the chamber water level detection unit 17, and the detected water level of the condensed water chamber 13 is the condensed water chamber 13. When the water level is equal to or higher than the lower limit water level La, the open / closed state of the first supply valve 15 is controlled based on the magnitude relationship between the head differential pressure P (h1) and the gas pressure (sweeping pressure P) described above, and the detected condensation When the water level of the water chamber 13 is less than the lower limit water level La, the first supply valve 15 is controlled to be closed.

With the above configuration, only when a sufficient amount of condensed water Wa for stably pumping and supplying the condensed water Wa to the scrubber 11a is stored in the condensed water chamber 13, the condensed water Wa is condensed via the first water supply pipe 14. The water chamber 13 and the scrubber 11a can be communicated with each other. Therefore, it is possible to prevent the combustion gas after cooling from leaking to the scrubber 11a via the condensed water chamber 13 and the first water supply pipe 14, and as a result, the combustion gas supplied to the scavenging trunk 2b is used for combustion. It is possible to suppress a decrease in the gas pressure of the gas, that is, a decrease in the sweep pressure P of the engine body 2.

Further, in the exhaust gas treatment device 10 and the water supply method according to the first embodiment of the present invention, the water level of the water treatment tank 18a is detected by the tank water level detection unit 18b, and the detected water level of the water treatment tank 18a is water treatment. When the water level is less than the upper limit water level Hb of the tank 18a, the open / closed state of the first supply valve 15 is controlled based on the magnitude relationship between the head differential pressure P (h1) and the gas pressure described above, and the detected water treatment is performed. When the water level of the tank 18a is equal to or higher than the upper limit water level Hb, the first supply valve 15 is controlled to be closed.

With the above configuration, the first water supply pipe 14 is used before the amount of scrubber water circulated between the EGR device 11 and the water treatment device 18 becomes excessive with respect to the purification treatment capacity of the water treatment device 18. The state of communication between the condensed water chamber 13 and the scrubber 11a can be cut off. As a result, since it is possible to prevent the situation where the condensed water Wa is unnecessarily pumped and supplied to the scrubber 11a, the condensed water Wa can be efficiently pumped and supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14.

(Embodiment 2)
Next, the second embodiment of the present invention will be described. In the above-described first embodiment, the supply destination device of the condensed water Wa is the scrubber 11a of the EGR device 11, but in the second embodiment, the supply destination device of the condensed water Wa is the recovery tank 11d of the EGR device 11.

FIG. 3 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the second embodiment of the present invention is applied. As shown in FIG. 3, the marine diesel engine 1A according to the second embodiment includes an exhaust gas treatment device 20 in place of the exhaust gas treatment device 10 of the marine diesel engine 1 according to the first embodiment described above. The exhaust gas treatment device 20 according to the second embodiment includes a second water supply pipe 24 in place of the first water supply pipe 14 of the exhaust gas treatment device 10 according to the first embodiment described above, and a second water supply pipe 24 in place of the first supply valve 15. A supply valve 25 is provided, and a control device 29 is provided in place of the control device 19. In the second embodiment, the device to which the condensed water Wa is supplied is not the scrubber 11a but the recovery tank 11d. That is, the scrubber 11a is not provided with a pipe (first water supply pipe 14) leading to the condensed water chamber 13. Other configurations are the same as those in the first embodiment, and the same components are designated by the same reference numerals.

The second water supply pipe 24 is an example of a water supply pipe for supplying the condensed water Wa stored in the condensed water chamber 13 to the supply destination device. As shown in FIG. 3, the second water supply pipe 24 is arranged so as to communicate the condensed water chamber 13 and the recovery tank 11d, which is an example of the supply destination device. Specifically, the second water supply pipe 24 has an inlet end connected to a predetermined portion of the condensed water chamber 13 and an outlet end connected to a water supply port of the recovery tank 11d, and is located between the condensed water chamber 13 and the recovery tank 11d. The head difference is arranged so as to be the head difference h2 shown in FIG. In the second embodiment, as shown in FIG. 3, the water supply port to which the outlet end of the second water supply pipe 24 of the recovery tank 11d is connected is formed on the side wall portion near the upper end of the recovery tank 11d. The inlet end of the second water supply pipe 24 is connected to a predetermined portion (for example, a side wall portion near the bottom) of the condensed water chamber 13 as in the first water supply pipe 14 in the first embodiment described above. The condensed water Wa is pressure-fed from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24 by utilizing the gas pressure accumulated in the condensed water chamber 13. As a result, the condensed water Wa is supplied to the recovery tank 11d.

In the second embodiment, the head difference h2 between the condensed water chamber 13 and the recovery tank 11d is the height difference between the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24, as shown in FIG. For example, the water level of the condensed water chamber 13 is a position in the height direction of the liquid level Sa of the condensed water Wa stored in the condensed water chamber 13. The outlet water level of the second water supply pipe 24 is a position in the height direction of the upper end of the inner wall at the outlet portion (water supply port of the recovery tank 11d) of the second water supply pipe 24. The reference positions of the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24 are the same as each other, for example, the bottom surface of the condensed water chamber 13.

Further, the head difference h2 is set so that the condensed water Wa can be pumped from the condensed water chamber 13 to the recovery tank 11d by utilizing the gas pressure in the condensed water chamber 13 during a desired period. For example, when the supply destination device is the recovery tank 11d of the EGR device 11, the head difference h2 is set so that the condensed water Wa can be pumped to the recovery tank 11d during the operation of the EGR device 11. In the second embodiment, the operating conditions of the EGR device 11, the reference value of the engine load, and the gas pressure in the condensed water chamber 13 are the same as those of the first embodiment described above. Therefore, the head difference h2 is the height difference between the head of the lower supply source device and the head of the higher supply destination device that can pump water using the sweep pressure P when the engine load is the above reference value. It is set to the following (for example, 3 m or less).

The second supply valve 25 is an example of a supply valve that opens or closes the water supply pipe for pumping the condensed water Wa to the supply destination device. In the second embodiment, as shown in FIG. 3, the second supply valve 25 is provided in the middle of the second water supply pipe 24. The second supply valve 25 is driven to open and close under the control of the control device 29, thereby opening or closing the second water supply pipe 24.

The control device 29 is an example of a device that controls the execution and stop of the water supply of the exhaust gas treatment device 20. In the second embodiment, the control device 29 controls the opening / closing drive of the second supply valve 25 provided in the second water supply pipe 24 that communicates the condensed water chamber 13 and the recovery tank 11d. The control device 29 is the same as the control device 19 in the first embodiment described above, except that the opening / closing drive of the second supply valve 25 is controlled instead of the first supply valve 15.

For example, the control device 29 determines the magnitude relationship between the head differential pressure P (h2) between the condensed water chamber 13 and the recovery tank 11d and the gas pressure (for example, sweep pressure P) detected by the pressure detecting unit 16. When the detected gas pressure is larger than the head differential pressure P (h2), the control device 29 controls the second supply valve 25 to be in the open state, and the detected gas pressure is equal to or less than the head differential pressure P (h2). If, the second supply valve 25 is controlled to be in the closed state.

Here, the head difference h2 increases or decreases in the same manner as the head difference h1 in the above-described first embodiment. In the second embodiment, as an example of the head difference h2, as in the first embodiment, the head difference (that is, the maximum value of the head difference) when the liquid level Sa of the condensed water Wa is located at the lower limit water level La of the condensed water chamber 13. ) Is used. The head differential pressure P (h2) is a pressure corresponding to the maximum value within a predetermined range of the head difference h2 that can be taken between the condensed water chamber 13 and the recovery tank 11d. Alternatively, the chamber water level detection unit 17 is configured to continuously or intermittently detect the water level of the condensed water chamber 13 at predetermined time intervals, and the head differential pressure P (h2) is detected by the chamber water level detection unit 17. The pressure may be a pressure corresponding to the head difference h2 between the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24.

Further, in the control device 29, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is equal to or higher than the lower limit water level La of the condensed water chamber 13, all the supply valves (second supply valve in the second embodiment). Regarding 25), the open / closed state is controlled based on the magnitude relationship between the above-mentioned head differential pressure P (h2) and the detected gas pressure. On the other hand, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is less than the lower limit water level La of the condensed water chamber 13, the control device 29 closes all the supply valves (second supply valve 25). To control.

Further, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is less than the upper limit water level Hb of the water treatment tank 18a, the control device 29 applies to all the supply valves (second supply valve 25). The open / closed state is controlled based on the magnitude relationship between the head differential pressure P (h2) described above and the detected gas pressure. On the other hand, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is equal to or higher than the upper limit water level Hb of the water treatment tank 18a, the control device 29 closes all the supply valves (second supply valve 25). Control to closed state.

Further, the control device 29 describes all the supply valves (second supply valve 25) when the engine load of the engine body 2 is equal to or higher than the above-mentioned reference value, that is, when the EGR device 11 is in operation. The open / closed state is controlled based on the magnitude relationship between the head differential pressure P (h2) and the detected gas pressure. On the other hand, the control device 29 closes all the supply valves (second supply valve 25) when the engine load of the engine body 2 is less than the above-mentioned reference value, that is, when the EGR device 11 is stopped. To control.

Next, the water supply method according to the second embodiment of the present invention will be described. The water supply method according to the second embodiment is a water supply method applied to the marine diesel engine 1A shown in FIG. In this water supply method, the exhaust gas treatment device 20 according to the second embodiment utilizes the accumulated pressure in the condensed water chamber 13 by appropriately performing each treatment substantially the same as steps S101 to S108 illustrated in FIG. The condensate water Wa is supplied or stopped to the recovery tank 11d, which is an example of the supply destination device. Specifically, in the water supply method according to the second embodiment, steps S101 to S105 are the same as those in the first embodiment, and steps S106 to S108 are different from the first embodiment. Hereinafter, only each process of steps S106 to S108 in the second embodiment will be described.

In step S106 in the second embodiment, the exhaust gas treatment device 20 determines the magnitude relationship between the gas pressure accumulated in the condensed water chamber 13 and the head differential pressure P (h2). The head differential pressure P (h2) is a pressure corresponding to the head difference h2 (see FIG. 3) between the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24. Specifically, in step S106, the control device 29 receives an electric signal from the pressure detection unit 16, and the detection pressure (sweeping pressure P in the second embodiment) and the head differential pressure indicated by the received electric signal. Compare with P (h2). As a result, the control device 29 determines the magnitude relationship between the sweep pressure P and the head differential pressure P (h2). The process of step S106 in the second embodiment is the same as that of the first embodiment except that the comparison target with the sweep pressure P is the head differential pressure P (h2) as described above.

Further, in step S107 in the second embodiment, the exhaust gas treatment device 20 opens the second supply valve 25 and pumps the condensed water Wa to the supply destination device. Specifically, in step S107, the control device 29 controls the second supply valve 25 in the open state. The second supply valve 25 is opened and driven based on the control of the control device 29, thereby opening the second water supply pipe 24. As a result, the exhaust gas treatment device 20 pumps the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24 by utilizing the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13. Supply. The process of step S106 in the second embodiment is the same as that of the first embodiment except that the control target is the second supply valve 25 and the supply destination device is the recovery tank 11d as described above.

Further, in step S108 in the second embodiment, the exhaust gas treatment device 20 closes the second supply valve 25. Specifically, in step S108, the control device 29 controls the second supply valve 25 in the closed state. The second supply valve 25 is closed and driven under the control of the control device 29, thereby closing the second water supply pipe 24. As a result, the exhaust gas treatment device 20 stops the pumping supply of the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d. The process of step S108 in the second embodiment is the same as that of the first embodiment except that the control target is the second supply valve 25 and the supply destination device is the recovery tank 11d as described above.

In the second embodiment, the exhaust gas treatment device 20 returns to step S101 in the same manner as in the first embodiment after executing the above-mentioned step S107 or step S108, and repeats the processes after this step S101.

As described above, in the exhaust gas treatment device 20 and the water supply method according to the second embodiment of the present invention, the recovery tank 11d of the EGR device 11 is used as the supply destination device, and the condensed water chamber 13 and the recovery tank 11d are communicated with each other. The second water supply pipe 24 is arranged so that the head difference between the condensed water chamber 13 and the recovery tank 11d is the head difference h2 shown in FIG. 3, and the gas pressure accumulated in the condensed water chamber 13 is used. Then, the condensed water Wa is pumped from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24. Further, a second supply valve 25 is provided in the second water supply pipe 24, and the open / closed state of the second supply valve 25 is controlled by the control device 29 as in the case of the first supply valve 15 in the first embodiment. .. Others are configured in the same manner as in the first embodiment.

Therefore, the supply destination device of the condensed water Wa is replaced from the scrubber 11a with the recovery tank 11d, and the head difference h1 and the head differential pressure P (h1) between the condensed water chamber 13 and the scrubber 11a are replaced with the condensed water chamber 13 and the recovery tank 11d. In the embodiment in which the head difference h2 and the head differential pressure P (h2) are replaced with each other, the same action and effect as those of the above-described first embodiment can be enjoyed, and the recovery tank can be used instead of the cleaning effect of the scrubber 11a itself in the first embodiment. Condensed water Wa can be efficiently pumped and supplied to 11d so as to make up for the shortage of scrubber water.

(Embodiment 3)
Next, the third embodiment of the present invention will be described. In the above-described first and second embodiments, the supply destination device of the condensed water Wa is either the scrubber 11a of the EGR device 11 or the recovery tank 11d, but in the third embodiment, the supply destination device of the condensed water Wa is the scrubber. 11a and recovery tank 11d.

FIG. 4 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the third embodiment of the present invention is applied. As shown in FIG. 4, the marine diesel engine 1B according to the third embodiment includes an exhaust gas treatment device 30 in place of the exhaust gas treatment device 10 of the marine diesel engine 1 according to the first embodiment described above. The exhaust gas treatment device 30 according to the third embodiment includes a second water supply pipe 24 in addition to the first water supply pipe 14 of the exhaust gas treatment device 10 according to the first embodiment described above, and is in the middle of the second water supply pipe 24. A second supply valve 25 is provided in the portion, and a control device 39 is provided in place of the control device 19. In the third embodiment, the device to which the condensed water Wa is supplied is the scrubber 11a and the recovery tank 11d. Other configurations are the same as those in the first embodiment, and the same components are designated by the same reference numerals.

In the third embodiment, as shown in FIG. 4, the water supply pipe that communicates the condensed water chamber 13 and the condensate water supply destination device corresponds to a plurality of supply destination devices, and has a head difference with respect to the condensate water chamber 13. Are provided so as to be different from each other. Specifically, as an example of these plurality of water supply pipes, the first water supply pipe 14 and the second water supply pipe 24 have head differences h1 and h2 with respect to the condensed water chamber 13 corresponding to the scrubber 11a and the recovery tank 11d. It is provided differently.

The first water supply pipe 14 is the same as the above-described first embodiment except that the second water supply pipe 24 is connected to the middle part. As shown in FIG. 4, the second water supply pipe 24 is arranged so as to communicate the condensed water chamber 13 and the recovery tank 11d via the first water supply pipe 14. Specifically, the second water supply pipe 24 has an inlet end connected to the middle part of the first water supply pipe 14 and an outlet end connected to the water supply port of the recovery tank 11d, and is between the condensed water chamber 13 and the recovery tank 11d. The head difference is arranged so as to be the head difference h2 as in the second embodiment. The second water supply pipe 24 is the same as the above-described second embodiment except that the second water supply pipe 24 is branched from the middle portion of the first water supply pipe 14 as shown in FIG. In the third embodiment, the condensed water Wa is pumped and supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14 by utilizing the gas pressure accumulated in the condensed water chamber 13. Further, the condensed water Wa is pressure-fed and supplied from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24 by utilizing the gas pressure accumulated in the condensed water chamber 13.

Further, as shown in FIG. 4, the head difference h1 between the condensed water chamber 13 and the scrubber 11a in the third embodiment is the same as that in the first embodiment described above. The head difference h2 between the condensed water chamber 13 and the recovery tank 11d in the third embodiment is the same as that in the second embodiment described above. In particular, when the supply destination device is the scrubber 11a and the recovery tank 11d of the EGR device 11, the head differences h1 and h2 can appropriately pump the condensed water Wa to the scrubber 11a and the recovery tank 11d during the operation of the EGR device 11. Is set to. That is, these head differences h1 and h2 are similar to those of the first and second embodiments, and are of a lower supply source device capable of pumping water by using the sweep pressure P when the engine load is the above reference value. The height difference between the head and the head of the higher supply destination device (for example, 3 m or less) is set. In the third embodiment, since the scrubber 11a is arranged higher than the recovery tank 11d, the head difference h1 corresponding to the scrubber 11a is larger than the head difference h2 corresponding to the recovery tank 11d. Therefore, the magnitude relationship between these head differences h1 and h2 and the height difference is such that height difference ≧ head difference h1> head difference h2.

On the other hand, in the third embodiment, as shown in FIG. 4, a supply valve is provided in each of the plurality of water supply pipes. Specifically, as an example of these plurality of supply valves, the first water supply pipe 14 is provided with the first supply valve 15, and the second water supply pipe 24 is provided with the second supply valve 25. The first supply valve 15 is the same as the above-described first embodiment, and the second supply valve 25 is the same as the above-mentioned second embodiment. In the third embodiment, each opening / closing drive of the first supply valve 15 and the second supply valve 25 is controlled by the control device 39.

The control device 39 is an example of a device that controls the execution and stop of the water supply of the exhaust gas treatment device 30. In the third embodiment, the control device 39 controls each opening / closing drive of the first supply valve 15 and the second supply valve 25 described above. The control device 39 is the same as the control device 19 in the first embodiment described above, except that the objects of drive control are the first supply valve 15 and the second supply valve 25.

For example, the control device 39 has a head differential pressure between the water level of the condensed water chamber 13 and a plurality of water supply pipes (first water supply pipe 14 and second water supply pipe 24 in the third embodiment) (head difference in the third embodiment). The magnitude relationship between the pressures P (h1) and P (h2)) and the gas pressure (for example, sweep pressure P) detected by the pressure detection unit 16 is determined. The control device 39 selects the open / closed state of the first supply valve 15 and the second supply valve 25 based on the magnitude relationship between the head differential pressures P (h1) and P (h2) and the detected gas pressure. Control.

In the third embodiment, the head differential pressure P (h1) corresponding to the head difference h1 between the water level of the condensed water chamber 13 and the outlet water level of the first water supply pipe 14 is the same as that of the first embodiment described above. Further, the head differential pressure P (h2) corresponding to the head difference h2 between the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24 is the same as that of the second embodiment described above.

Further, in the control device 39, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is equal to or higher than the lower limit water level La of the condensed water chamber 13, all the supply valves (the first supply valve in the third embodiment). The open / closed state of the 15 and the second supply valve 25) is controlled based on the magnitude relationship between the head differential pressures P (h1) and P (h2) described above and the detected gas pressure. On the other hand, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is less than the lower limit water level La of the condensed water chamber 13, the control device 39 has all the supply valves (first supply valve 15 and second supply). The valve 25) is controlled to be closed.

Further, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is equal to or higher than the lower limit water level Lb of the water treatment tank 18a and lower than the upper limit water level Hb, the control device 39 has all the supply valves (first). Regarding the supply valve 15 and the second supply valve 25), the open / closed state is controlled based on the magnitude relationship between the head differential pressures P (h1) and P (h2) described above and the detected gas pressure. On the other hand, in the control device 39, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is equal to or higher than the upper limit water level Hb of the water treatment tank 18a, all the supply valves (first supply valve 15 and first supply valve 39) 2 The supply valve 25) is controlled to be closed.

Further, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is less than the lower limit water level Lb of the water treatment tank 18a, the control device 39 has the detected gas among the plurality of supply valves. At least one supply valve (at least one of the first supply valve 15 and the second supply valve 25 in the third embodiment) that satisfies the condition that the pressure is larger than the head differential pressure is controlled to be in the open state.

Further, in the control device 39, when the engine load of the engine body 2 is equal to or higher than the above-mentioned reference value, that is, when the EGR device 11 is in operation, all the supply valves (first supply valve 15 and second supply valve) are used. Regarding 25), the open / closed state is controlled based on the magnitude relationship between the above-mentioned head differential pressures P (h1) and P (h2) and the detected gas pressure. On the other hand, in the control device 39, when the engine load of the engine body 2 is less than the above-mentioned reference value, that is, when the EGR device 11 is stopped, all the supply valves (first supply valve 15 and second supply) are supplied. The valve 25) is controlled to be closed.

Next, the water supply method according to the third embodiment of the present invention will be described. FIG. 5 is a flow chart showing an example of the water supply method according to the third embodiment of the present invention. The water supply method according to the third embodiment is a water supply method applied to the marine diesel engine 1B illustrated in FIG. In this water supply method, the exhaust gas treatment device 30 according to the third embodiment appropriately performs each of the treatments of steps S301 to S314 illustrated in FIG. 5, thereby utilizing the accumulated pressure in the condensed water chamber 13. The supply or supply of the condensed water Wa to the scrubber 11a and the recovery tank 11d, which are examples of the supply destination device, is performed.

Specifically, in the water supply method according to the third embodiment, the exhaust gas treatment device 30 collects condensed water under the scavenging pressure of the engine body 2 (step S301), and then the scavenging pressure. Condensed water is stored together with P (step S302), and then it is determined whether or not the EGR device 11 is in operation (step S303). These steps S301 to S303 are performed in the same manner as steps S101 to S103 in the above-described first embodiment.

When it is determined in step S303 described above that the EGR device 11 is in operation (step S303, Yes), in the exhaust gas treatment device 30, whether the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La of the condensed water chamber 13. Whether or not it is determined (step S304). This step S304 is performed in the same manner as step S104 in the above-described first embodiment.

When it is determined in step S304 that the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La (step S304, Yes), the exhaust gas treatment device 30 determines the water level of the water treatment tank 18a (step S305).

In step S305, the exhaust gas treatment device 30 detects the water level of the water treatment tank 18a by the tank water level detection unit 18b. Here, the water level of the water treatment tank 18a is the position in the height direction of the liquid level Sb of the scrubber water Wc in the water treatment tank 18a. For example, the upper limit water level Hb or more, the lower limit water level Lb or more and less than the upper limit water level Hb. , The lower limit water level is less than Lb. The tank water level detection unit 18b transmits an electric signal indicating the detection result of the water level of the water treatment tank 18a to the control device 39. The control device 39 receives an electric signal from the tank water level detection unit 18b, and determines the water level of the water treatment tank 18a based on the detection result of the water level of the water treatment tank 18a indicated by the received electric signal. To do.

Specifically, when the control device 39 receives an electric signal from the tank water level detection unit 18b indicating a detection result that the water level of the water treatment tank 18a is equal to or higher than the upper limit water level Hb, the water level of the water treatment tank 18a is raised. It is judged that the upper limit water level is Hb or higher. Further, when the control device 39 receives an electric signal from the tank water level detection unit 18b indicating a detection result that the water level of the water treatment tank 18a is equal to or higher than the lower limit water level Lb and lower than the upper limit water level Hb, the control device 39 receives the electric signal of the water treatment tank 18a. It is determined that the water level is equal to or higher than the lower limit water level Lb and lower than the upper limit water level Hb. Further, when the control device 39 receives an electric signal from the tank water level detection unit 18b indicating a detection result that the water level of the water treatment tank 18a is lower than the lower limit water level Lb, the water level of the water treatment tank 18a is the lower limit water level Lb. Judge that it is less than.

In the third embodiment, when the water level of the water treatment tank 18a is less than the upper limit water level Hb, the exhaust gas treatment device 30 is detected by the above-mentioned head differential pressures P (h1) and P (h2) and the pressure detection unit 16. The open / closed state of the first supply valve 15 and the second supply valve 25 is selectively controlled based on the magnitude relationship with the gas pressure.

Specifically, when it is determined in step S305 described above that the water level of the water treatment tank 18a is less than the lower limit water level Lb (step S305, Sb <Lb), the exhaust gas treatment device 30 is among the plurality of supply valves. At least one supply valve that satisfies the condition that the gas pressure detected by the pressure detection unit 16 is larger than the head differential pressure (hereinafter, referred to as a pressure condition) is controlled to be in an open state. More specifically, the control device 39 has a magnitude of the gas pressure (= sweep pressure P) and the head differential pressure P (h1) accumulated in the condensed water chamber 13 as in step S106 in the first embodiment described above. The relationship is determined (step S306). In step S306, when the detected sweep pressure P is larger than the head differential pressure P (h1) (step S306, Yes), both the first supply valve 15 and the second supply valve 25 have the pressures described above. Satisfy the conditions. In this case, the exhaust gas treatment device 30 opens the first supply valve 15 and the second supply valve 25 to pump the condensed water Wa to the supply destination device (step S307).

In step S307, the control device 39 controls the first supply valve 15 and the second supply valve 25 in the open state. The first supply valve 15 is driven to open under the control of the control device 39, thereby opening the first water supply pipe 14. As a result, the exhaust gas treatment device 30 uses the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 to pump and supply the condensed water Wa from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14. To do. In parallel with this, the second supply valve 25 is driven to open under the control of the control device 39, thereby opening the second water supply pipe 24. As a result, the exhaust gas treatment device 30 uses the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 to pump the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24. Supply.

On the other hand, when it is determined in step S305 described above that the water level of the water treatment tank 18a is equal to or higher than the lower limit water level Lb and lower than the upper limit water level Hb (step S305, Lb ≦ Sb <Hb), the exhaust gas treatment device 30 is used for all. The open / closed state of the supply valve is controlled based on the magnitude relationship between the head differential pressure and the detected gas pressure.

Specifically, the control device 39 has a magnitude relationship between the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 and the head differential pressure P (h1), as in step S106 in the first embodiment described above. Is determined (step S308). In step S308, when the detected sweep pressure P is larger than the head differential pressure P (h1) (step S308, Yes), the exhaust gas treatment device 30 opens the first supply valve 15 to supply the condensed water Wa. It is pumped to the destination device (step S309). This step S309 is performed in the same manner as step S107 in the above-described first embodiment. As a result, the condensed water Wa is pumped and supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14.

On the other hand, when the detected sweep pressure P is equal to or less than the head differential pressure P (h1) in step S308 described above (steps S308, No), the exhaust gas treatment device 30 closes the first supply valve 15 (step S310). .. This step S310 is performed in the same manner as step S108 in the above-described first embodiment.

After executing step S310, the exhaust gas treatment device 30 determines the magnitude relationship between the gas pressure accumulated in the condensed water chamber 13 and the head differential pressure P (h2) (step S311). The head differential pressure P (h2) is a pressure corresponding to the head difference h2 (see FIG. 4) between the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24. In step S311 the control device 39 compares the gas pressure detected by the pressure detection unit 16 in step S306 or step S308 described above with the head differential pressure P (h2). As a result, the control device 39 determines the magnitude relationship between these gas pressures (sweeping pressure P in the third embodiment) and the head differential pressure P (h2).

In step S311 described above, when the detected sweep pressure P is larger than the head differential pressure P (h2) (steps S311, Yes), the exhaust gas treatment device 30 opens the second supply valve 25 to release the condensed water Wa. It is pumped to the supply destination device (step S312). In step S312, the control device 39 controls the second supply valve 25 in the open state. The second supply valve 25 is opened and driven based on the control of the control device 39, thereby opening the second water supply pipe 24. As a result, the exhaust gas treatment device 30 uses the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 to pump the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24. Supply.

On the other hand, when the detected sweep pressure P is equal to or less than the head differential pressure P (h2) in step S311 described above (steps S311, No), the exhaust gas treatment device 30 closes the second supply valve 25 (step S313). .. In step S313, the control device 39 controls the second supply valve 25 in the closed state. The second supply valve 25 is closed and driven under the control of the control device 39, thereby closing the second water supply pipe 24. As a result, the exhaust gas treatment device 30 stops the pumping supply of the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d.

On the other hand, when it is determined in step S305 described above that the water level of the water treatment tank 18a is equal to or higher than the upper limit water level Hb (step S305, Sb ≧ Hb), the exhaust gas treatment device 30 closes all the supply valves (step S314). ). In step S314, the control device 39 controls the first supply valve 15 and the second supply valve 25 in the closed state. The first supply valve 15 is closed and driven under the control of the control device 39, thereby closing the first water supply pipe 14. In parallel with this, the second supply valve 25 is closed and driven under the control of the control device 39, thereby closing the second water supply pipe 24. As a result, the exhaust gas treatment device 30 stops the pumping supply of the condensed water Wa from the condensed water chamber 13 to the scrubber 11a and the recovery tank 11d.

After executing the above-mentioned step S307, step S309, step S312, step S313 or step S314, the exhaust gas treatment device 30 returns to the above-mentioned step S301 and repeats the processes after this step S301. If it is determined in step S303 described above that the EGR device 11 is not in operation (steps S303, No), the exhaust gas treatment device 30 proceeds to step S314 described above, and repeats the processes after step S314. Further, when it is determined in step S304 described above that the water level of the condensed water chamber 13 is not equal to or higher than the lower limit water level La (steps S304, No), the exhaust gas treatment device 30 proceeds to step S314 described above, and proceeds to step S314 and subsequent steps. Repeat the process. When the gas pressure (= sweep pressure P) detected in step S306 described above is equal to or less than the head differential pressure P (h1) (steps S306, No), the exhaust gas treatment device 30 proceeds to step S310 described above. The processing after this step S310 is repeated.

As described above, in the exhaust gas treatment device 30 and the water supply method according to the third embodiment of the present invention, the scrubber 11a and the recovery tank 11d of the EGR device 11 are used as a plurality of supply destination devices via the first water supply pipe 14. The condensed water chamber 13 and the scrubber 11a are communicated with each other, and the condensed water chamber 13 and the recovery tank 11d are communicated with each other via the second water supply pipe 24. Condensed water Wa is appropriately pumped from the water chamber 13 to the scrubber 11a and the recovery tank 11d, and the others are configured in the same manner as in the first and second embodiments. Therefore, the same operation and effect as in the first embodiment and the same operation and effect as in the second embodiment are enjoyed, and water is supplied to the plurality of supply destination devices while having a plurality of supply destination devices for the condensed water Wa. It is possible to save the installation space of equipment such as chambers and pipes required for this water supply function without deteriorating the function.

(Embodiment 4)
Next, the fourth embodiment of the present invention will be described. In the above-described third embodiment, the supply destination device of the condensed water Wa is the scrubber 11a and the recovery tank 11d of the EGR device 11, but in the fourth embodiment, the supply destination device of the condensed water Wa is further other than the EGR device 11. Equipment (specifically, the water treatment tank of the water treatment equipment) has been added.

FIG. 6 is a schematic view showing a configuration example of a marine diesel engine to which the exhaust gas treatment device according to the fourth embodiment of the present invention is applied. As shown in FIG. 6, the marine diesel engine 1C according to the fourth embodiment includes an exhaust gas treatment device 40 in place of the exhaust gas treatment device 30 of the marine diesel engine 1B according to the third embodiment described above. The exhaust gas treatment device 40 according to the fourth embodiment includes a third water supply pipe 44 in addition to the first water supply pipe 14 and the second water supply pipe 24 of the exhaust gas treatment device 30 according to the third embodiment described above. 3 A third supply valve 45 is provided in the middle of the water supply pipe 44, and a control device 49 is provided in place of the control device 39. In the fourth embodiment, the supply destination device of the condensed water Wa is the scrubber 11a and the recovery tank 11d of the EGR device 11 and the water treatment tank 18a of the water treatment device 18. Other configurations are the same as those in the third embodiment, and the same components are designated by the same reference numerals.

In the fourth embodiment, as shown in FIG. 6, the water supply pipe that communicates the condensed water chamber 13 and the condensate water supply destination device corresponds to a plurality of supply destination devices, and has a head difference with respect to the condensate water chamber 13. Are provided so as to be different from each other. Specifically, as an example of these plurality of water supply pipes, the first water supply pipe 14, the second water supply pipe 24, and the third water supply pipe 44 correspond to the scrubber 11a, the recovery tank 11d, and the water treatment tank 18a. The head differences h1, h2, and h3 with respect to the condensed water chamber 13 are provided so as to be different from each other.

The first water supply pipe 14 is the same as the above-described third embodiment except that the second water supply pipe 24 and the third water supply pipe 44 are connected to the middle part. The second water supply pipe 24 is the same as that of the third embodiment described above. Further, the head difference h1 corresponding to the first water supply pipe 14 and the head difference h2 corresponding to the second water supply pipe 24 are the same as those in the third embodiment described above.

The third water supply pipe 44 is an example of a water supply pipe for supplying the condensed water Wa stored in the condensed water chamber 13 to the supply destination device. As shown in FIG. 6, the third water supply pipe 44 is arranged so as to communicate the condensed water chamber 13 and the water treatment tank 18a, which is an example of the supply destination device. Specifically, the third water supply pipe 44 has an inlet end connected to the middle part of the first water supply pipe 14 and an outlet end connected to the water supply port of the water treatment tank 18a, and the condensed water chamber 13 and the water treatment tank. The head difference from 18a is arranged so as to be the head difference h3 shown in FIG. In the fourth embodiment, as shown in FIG. 6, the water supply port to which the outlet end of the third water supply pipe 44 of the water treatment tank 18a is connected is formed on the side wall portion near the upper end of the water treatment tank 18a. ing. The condensed water Wa is pressure-fed from the condensed water chamber 13 to the water treatment tank 18a through the third water supply pipe 44 by utilizing the gas pressure accumulated in the condensed water chamber 13. As a result, the condensed water Wa is supplied to the water treatment tank 18a.

In the fourth embodiment, the head difference h3 between the condensed water chamber 13 and the water treatment tank 18a is the height difference between the water level of the condensed water chamber 13 and the outlet water level of the third water supply pipe 44, as shown in FIG. Become. For example, the water level of the condensed water chamber 13 is a position in the height direction of the liquid level Sa of the condensed water Wa stored in the condensed water chamber 13. The outlet water level of the third water supply pipe 44 is a position in the height direction of the upper end of the inner wall at the outlet portion of the third water supply pipe 44 (the water supply port of the water treatment tank 18a). The reference positions of the water level of the condensed water chamber 13 and the outlet water level of the third water supply pipe 44 are the same as each other, for example, the bottom surface of the condensed water chamber 13.

Further, the head difference h3 is set so that the condensed water Wa can be pumped from the condensed water chamber 13 to the water treatment tank 18a by utilizing the gas pressure in the condensed water chamber 13 during a desired period. For example, when the water treatment tank 18a of the water treatment device 18 that purifies the scrubber water of the EGR device 11 is included as the supply destination device of the condensed water Wa, the head difference h3 is treated with water during the operation of the EGR device 11. It is set so that the condensed water Wa can be pumped to the tank 18a. In the fourth embodiment, the operating conditions of the EGR device 11, the reference value of the engine load, and the gas pressure in the condensed water chamber 13 are the same as those of the third embodiment described above. Therefore, the head difference h3 and the above-mentioned head differences h1 and h2 are higher than the head of the lower source device capable of pumping water by using the sweep pressure P when the engine load is the above reference value. It is set to be less than or equal to the height difference (for example, 3 m or less) from the head of the supply destination device. In the fourth embodiment, for example, of the three head differences h1, h2, and h3, the head difference h1 corresponding to the scrubber 11a is larger than the other head differences h2 and h3. Further, the head difference h2 corresponding to the recovery tank 11d is larger than the head difference h3 corresponding to the water treatment tank 18a. In this case, the magnitude relationship between these head differences h1, h2, h3 and the height difference is such that height difference ≧ head difference h1> head difference h2> head difference h3. In the present invention, the magnitude relation of the head differences h1, h2, and h3 is not limited to the above magnitude relation.

On the other hand, in the fourth embodiment, as shown in FIG. 6, a supply valve is provided in each of the plurality of water supply pipes. Specifically, as an example of these plurality of supply valves, the first water supply pipe 14 is provided with the first supply valve 15, the second water supply pipe 24 is provided with the second supply valve 25, and the third water supply pipe is provided. The 44 is provided with a third supply valve 45. The first supply valve 15 and the second supply valve 25 are the same as those in the third embodiment described above. The third supply valve 45 is an example of a supply valve that opens or closes a water supply pipe for pumping condensed water Wa to a supply destination device. In the fourth embodiment, as shown in FIG. 6, the third supply valve 45 is provided in the middle of the third water supply pipe 44. The first supply valve 15, the second supply valve 25, and the third supply valve 45 are each opened and closed under the control of the control device 49. As a result, the first supply valve 15 opens or closes the first water supply pipe 14, the second supply valve 25 opens or closes the second water supply pipe 24, and the third supply valve 45 opens or closes the third water supply pipe. The tube 44 is opened or closed.

The control device 49 is an example of a device that controls the execution and stop of the water supply of the exhaust gas treatment device 40. In the fourth embodiment, the control device 49 controls each opening / closing drive of the first supply valve 15, the second supply valve 25, and the third supply valve 45. The control device 49 is the same as the control device 39 in the third embodiment described above, except that the objects of drive control are the first supply valve 15, the second supply valve 25, and the third supply valve 45.

For example, the control device 49 is a head differential pressure between the water level of the condensed water chamber 13 and a plurality of water supply pipes (first water supply pipe 14, second water supply pipe 24, and third water supply pipe 44 in the present embodiment 4). In the fourth embodiment, the magnitude relationship between the head differential pressures P (h1), P (h2), P (h3)) and the gas pressure (for example, sweep pressure P) detected by the pressure detection unit 16 is determined. The control device 49 has a first supply valve 15 and a second supply valve 25 based on the magnitude relationship between these head differential pressures P (h1), P (h2), and P (h3) and the detected gas pressure. And the open / closed state of the third supply valve 45 is selectively controlled.

Here, the head difference h3 increases or decreases in the same manner as the head differences h1 and h2 in the third embodiment described above. In the fourth embodiment, as an example of the head difference h3, as in the third embodiment, the head difference (that is, the maximum value of the head difference) when the liquid level Sa of the condensed water Wa is located at the lower limit water level La of the condensed water chamber 13. ) Is used. The head differential pressure P (h3) is a pressure corresponding to the maximum value within a predetermined range of the head difference h3 that can be taken between the condensed water chamber 13 and the water treatment tank 18a. Alternatively, the chamber water level detection unit 17 is configured to continuously or intermittently detect the water level of the condensed water chamber 13 at predetermined time intervals, and the head differential pressure P (h3) is detected by the chamber water level detection unit 17. The pressure may be a pressure corresponding to the head difference h3 between the water level of the condensed water chamber 13 and the outlet water level of the third water supply pipe 44.

In the fourth embodiment, the head differential pressure P (h1) corresponding to the head difference h1 between the water level of the condensed water chamber 13 and the outlet water level of the first water supply pipe 14 is the same as that of the above-described first and third embodiments. is there. Further, the head differential pressure P (h2) corresponding to the head difference h2 between the water level of the condensed water chamber 13 and the outlet water level of the second water supply pipe 24 is the same as that of the above-described embodiments 2 and 3.

Further, in the control device 49, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is equal to or higher than the lower limit water level La of the condensed water chamber 13, all the supply valves (the first supply valve in the fourth embodiment) 15. The second supply valve 25 and the third supply valve 45) are in an open / closed state based on the magnitude relationship between the above-mentioned head differential pressures P (h1), P (h2), P (h3) and the detected gas pressure. Take control. On the other hand, when the water level of the condensed water chamber 13 detected by the chamber water level detecting unit 17 is less than the lower limit water level La of the condensed water chamber 13, the control device 49 provides all the supply valves (first supply valve 15, second supply). The valve 25 and the third supply valve 45) are controlled to be closed.

Further, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is equal to or higher than the lower limit water level Lb of the water treatment tank 18a and lower than the upper limit water level Hb, the control device 49 has all the supply valves (first). The supply valve 15, the second supply valve 25, and the third supply valve 45) are opened and closed based on the magnitude relationship between the above-mentioned head differential pressures P (h1), P (h2), and P (h3) and the detected gas pressure. Control the state. On the other hand, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is equal to or higher than the upper limit water level Hb of the water treatment tank 18a, the control device 49 has all the supply valves (first supply valve 15, first). 2 The supply valve 25 and the third supply valve 45) are controlled to be closed.

Further, when the water level of the water treatment tank 18a detected by the tank water level detection unit 18b is less than the lower limit water level Lb of the water treatment tank 18a, the control device 49 has the detected gas among the plurality of supply valves. At least one supply valve (at least one of the first supply valve 15, the second supply valve 25, and the third supply valve 45 in the present embodiment 4) that satisfies the condition that the pressure is larger than the head differential pressure is opened. Control.

Further, the control device 49 includes all supply valves (first supply valve 15, second supply valve) when the engine load of the engine body 2 is equal to or higher than the above-mentioned reference value, that is, when the EGR device 11 is in operation. The open / closed state of the 25 and the third supply valve 45) is controlled based on the magnitude relationship between the above-mentioned head differential pressures P (h1), P (h2), P (h3) and the detected gas pressure. On the other hand, the control device 49 has all the supply valves (first supply valve 15, second supply) when the engine load of the engine body 2 is less than the above-mentioned reference value, that is, when the EGR device 11 is stopped. The valve 25 and the third supply valve 45) are controlled to be closed.

Next, the water supply method according to the fourth embodiment of the present invention will be described. FIG. 7 is a flow chart showing an example of the water supply method according to the fourth embodiment of the present invention. The water supply method according to the fourth embodiment is a water supply method applied to the marine diesel engine 1C illustrated in FIG. In this water supply method, the exhaust gas treatment device 40 according to the fourth embodiment appropriately performs each of the treatments of steps S401 to S417 illustrated in FIG. 7, thereby utilizing the accumulated pressure in the condensed water chamber 13. The supply or supply of the condensed water Wa to the scrubber 11a, the recovery tank 11d, and the water treatment tank 18a, which are examples of the supply destination device, is performed.

Specifically, in the water supply method according to the fourth embodiment, the exhaust gas treatment device 40 collects condensed water under the scavenging pressure of the engine body 2 (step S401), and then the scavenging pressure. Condensed water is stored together with P (step S402), and then it is determined whether or not the EGR device 11 is in operation (step S403). These steps S401 to S403 are performed in the same manner as steps S301 to S303 in the third embodiment described above.

When it is determined in step S403 described above that the EGR device 11 is in operation (step S403, Yes), the exhaust gas treatment device 40 has the water level of the condensed water chamber 13 equal to or higher than the lower limit water level La of the condensed water chamber 13. It is determined whether or not (step S404). This step S404 is performed in the same manner as step S304 in the third embodiment described above.

When it is determined in step S404 that the water level of the condensed water chamber 13 is equal to or higher than the lower limit water level La (step S404, Yes), the exhaust gas treatment device 40 determines the water level of the water treatment tank 18a (step S405). This step S405 is performed in the same manner as step S305 in the third embodiment described above.

In the fourth embodiment, when the water level of the water treatment tank 18a is less than the upper limit water level Hb, the exhaust gas treatment device 40 detects the above-mentioned head differential pressures P (h1), P (h2), P (h3) and pressure. The open / closed state of the first supply valve 15, the second supply valve 25, and the third supply valve 45 is selectively controlled based on the magnitude relationship with the gas pressure detected by the unit 16.

Specifically, when it is determined in step S405 described above that the water level of the water treatment tank 18a is less than the lower limit water level Lb (steps S405 and Sb <Lb), the exhaust gas treatment device 40 is among the plurality of supply valves. At least one supply valve that satisfies the pressure condition that the gas pressure detected by the pressure detection unit 16 is larger than the head differential pressure is controlled to be in the open state. More specifically, the control device 49 has a magnitude of the gas pressure (= sweep pressure P) and the head differential pressure P (h1) accumulated in the condensed water chamber 13 as in step S306 in the third embodiment described above. Determine the relationship (step S406). In step S406, when the detected sweep pressure P is larger than the head differential pressure P (h1) (step S406, Yes), the first supply valve 15, the second supply valve 25, and the third supply valve 45 Both satisfy the above-mentioned pressure conditions. In this case, the exhaust gas treatment device 40 opens at least one of the first supply valve 15, the second supply valve 25, and the third supply valve 45, for example, the first supply valve 15 and the second supply valve 25, and condenses water. Wa is pumped to the destination device (step S407).

In step S407, the control device 49 controls the first supply valve 15 and the second supply valve 25 of the first supply valve 15, the second supply valve 25, and the third supply valve 45 to be in the open state. The first supply valve 15 is driven to open under the control of the control device 49, thereby opening the first water supply pipe 14. As a result, the exhaust gas treatment device 40 uses the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 to pump and supply the condensed water Wa from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14. To do. In parallel with this, the second supply valve 25 is driven to open under the control of the control device 49, thereby opening the second water supply pipe 24. As a result, the exhaust gas treatment device 40 pumps the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24 by utilizing the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13. Supply.

On the other hand, when the detected sweep pressure P is equal to or less than the head differential pressure P (h1) in step S406 described above (step S406, No), the exhaust gas treatment device 40 closes the first supply valve 15 (step S408). .. This step S408 is performed in the same manner as step S310 in the third embodiment described above. As a result, the pumping supply of the condensed water Wa from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14 is stopped.

After executing step S408, the exhaust gas treatment device 40 determines the magnitude relationship between the gas pressure accumulated in the condensed water chamber 13 and the head differential pressure P (h2) (step S409). This step S409 is performed in the same manner as step S311 in the third embodiment described above.

In step S409, when the detected sweep pressure P is larger than the head differential pressure P (h2) (step S409, Yes), the sweep pressure P and the head differential pressures P (h1) and P (h2) are combined. The magnitude relationship is head differential pressure P (h1) ≧ sweep pressure P> head differential pressure P (h2). That is, of the first supply valve 15, the second supply valve 25, and the third supply valve 45, the second supply valve 25 and the third supply valve 45 satisfy the above-mentioned pressure conditions. In this case, the exhaust gas treatment device 40 opens the second supply valve 25 and the third supply valve 45 to pump the condensed water Wa to the supply destination device (step S410).

In step S410, the control device 49 controls the second supply valve 25 and the third supply valve 45 in the open state. The second supply valve 25 is driven to open under the control of the control device 49, thereby opening the second water supply pipe 24. As a result, the exhaust gas treatment device 40 pumps the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24 by utilizing the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13. Supply. In parallel with this, the third supply valve 45 is driven to open under the control of the control device 49, thereby opening the third water supply pipe 44. As a result, the exhaust gas treatment device 40 utilizes the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 to condense water Wa from the condensed water chamber 13 to the water treatment tank 18a through the third water supply pipe 44. Is pumped and supplied.

On the other hand, when it is determined in step S405 described above that the water level of the water treatment tank 18a is equal to or higher than the lower limit water level Lb and lower than the upper limit water level Hb (step S405, Lb ≦ Sb <Hb), the exhaust gas treatment device 40 is used for all. The open / closed state of the supply valve is controlled based on the magnitude relationship between the head differential pressure and the detected gas pressure.

Specifically, the control device 49 has a magnitude relationship between the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 and the head differential pressure P (h1), as in step S308 in the third embodiment described above. Is determined (step S411). In step S411, when the detected sweep pressure P is larger than the head differential pressure P (h1) (step S411, Yes), the exhaust gas treatment device 40 opens the first supply valve 15 to supply the condensed water Wa. It is pumped to the destination device (step S412). This step S412 is performed in the same manner as in step S309 in the third embodiment described above. As a result, the condensed water Wa is pumped and supplied from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14.

On the other hand, when the detected sweep pressure P is equal to or less than the head differential pressure P (h1) in step S411 described above (step S411, No), the exhaust gas treatment device 40 closes the first supply valve 15 (step S413). .. This step S413 is performed in the same manner as step S310 in the third embodiment described above. As a result, the pumping supply of the condensed water Wa from the condensed water chamber 13 to the scrubber 11a through the first water supply pipe 14 is stopped.

After executing step S413, the exhaust gas treatment device 40 determines the magnitude relationship between the gas pressure accumulated in the condensed water chamber 13 and the head differential pressure P (h2) (step S414). This step S414 is performed in the same manner as step S311 in the third embodiment described above.

When the detected sweep pressure P is larger than the head differential pressure P (h2) in step S414 described above (step S414, Yes), the exhaust gas treatment device 40 opens the second supply valve 25 to release the condensed water Wa. It is pumped to the supply destination device (step S415). This step S415 is performed in the same manner as step S312 in the third embodiment described above. As a result, the condensed water Wa is pumped and supplied from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24.

On the other hand, when the detected sweep pressure P is equal to or less than the head differential pressure P (h2) in step S414 described above (step S414, No), the exhaust gas treatment device 40 closes the second supply valve 25 (step S416). .. This step S416 is performed in the same manner as step S313 in the third embodiment described above. As a result, the pumping supply of the condensed water Wa from the condensed water chamber 13 to the recovery tank 11d through the second water supply pipe 24 is stopped.

After executing step S416, the exhaust gas treatment device 40 determines the magnitude relationship between the gas pressure accumulated in the condensed water chamber 13 and the head differential pressure P (h3) (step S417). The head differential pressure P (h3) is a pressure corresponding to the head difference h3 (see FIG. 6) between the water level of the condensed water chamber 13 and the outlet water level of the third water supply pipe 44. In step S417, the control device 49 compares the gas pressure detected by the pressure detection unit 16 in step S406 or step S411 described above with the head differential pressure P (h3). Thereby, the control device 49 determines the magnitude relationship between these gas pressures (sweeping pressure P in the present embodiment 4) and the head differential pressure P (h3).

In step S417 described above, when the detected sweep pressure P is larger than the head differential pressure P (h3) (step S417, Yes), the exhaust gas treatment device 40 opens the third supply valve 45 to release the condensed water Wa. It is pumped to the supply destination device (step S418). In step S418, the control device 49 controls the third supply valve 45 in the open state. The third supply valve 45 is opened and driven based on the control of the control device 49, thereby opening the third water supply pipe 44. As a result, the exhaust gas treatment device 40 utilizes the gas pressure (= sweep pressure P) accumulated in the condensed water chamber 13 to condense water Wa from the condensed water chamber 13 to the water treatment tank 18a through the third water supply pipe 44. Is pumped and supplied.

On the other hand, when the detected sweep pressure P is equal to or less than the head differential pressure P (h3) in step S417 described above (step S417, No), the exhaust gas treatment device 40 closes the third supply valve 45 (step S419). .. In step S419, the control device 49 controls the third supply valve 45 in the closed state. The third supply valve 45 is closed and driven under the control of the control device 49, thereby closing the third water supply pipe 44. As a result, the exhaust gas treatment device 40 stops the pumping supply of the condensed water Wa from the condensed water chamber 13 to the water treatment tank 18a.

On the other hand, when it is determined in step S405 described above that the water level of the water treatment tank 18a is equal to or higher than the upper limit water level Hb (steps S405 and Sb ≧ Hb), the exhaust gas treatment device 40 closes all the supply valves (step S420). ). In step S420, the control device 49 controls the first supply valve 15, the second supply valve 25, and the third supply valve 45 in the closed state. The first supply valve 15 is closed and driven under the control of the control device 49, thereby closing the first water supply pipe 14. In parallel with this, the second supply valve 25 is closed and driven under the control of the control device 49, thereby closing the second water supply pipe 24. The third supply valve 45 is closed and driven under the control of the control device 49, thereby closing the third water supply pipe 44. As a result, the exhaust gas treatment device 40 stops the pumping supply of the condensed water Wa from the condensed water chamber 13 to the scrubber 11a, the recovery tank 11d, and the water treatment tank 18a.

After executing the above-mentioned step S407, step S410, step S412, step S415, step S418, step S419 or step S420, the exhaust gas treatment device 40 returns to the above-mentioned step S401 and repeats the processes after this step S401. If it is determined in step S403 described above that the EGR device 11 is not in operation (steps S403, No), the exhaust gas treatment device 40 proceeds to step S420 described above, and repeats the processes after step S420. Further, when it is determined in step S404 described above that the water level of the condensed water chamber 13 is not equal to or higher than the lower limit water level La (steps S404, No), the exhaust gas treatment device 40 proceeds to step S420 described above, and proceeds to step S420 and thereafter. Repeat the process. When the gas pressure (= sweep pressure P) detected in step S409 described above is equal to or less than the head differential pressure P (h2) (step S409, No), the exhaust gas treatment device 40 proceeds to step S416 described above. The processing after this step S416 is repeated.

As described above, in the exhaust gas treatment device 40 and the water supply method according to the fourth embodiment of the present invention, the scrubber 11a and the recovery tank 11d of the EGR device 11 and the water treatment tank 18a of the water treatment device 18 are plurality of. The condensed water chamber 13 and the scrubber 11a are communicated with each other via the first water supply pipe 14, the condensed water chamber 13 and the recovery tank 11d are communicated with each other via the second water supply pipe 24, and further. The condensed water chamber 13 and the water treatment tank 18a are communicated with each other via the third water supply pipe 44, and the gas pressure accumulated in the condensed water chamber 13 is utilized to perform the scrubber 11a, the recovery tank 11d and the recovery tank 11d from the condensed water chamber 13. Condensed water Wa is appropriately pumped to the water treatment tank 18a, and the others are configured in the same manner as in the third embodiment. Therefore, the same effects as those of the above-described third embodiment can be enjoyed, and the water supply function to the plurality of supply destination devices can be reduced while the number of the condensate water Wa supply destination devices is larger than that of the third embodiment. Therefore, the installation space for equipment such as chambers and pipes required for this water supply function can be saved.

In the above-described first and second embodiments, the scrubber 11a or the recovery tank 11d of the EGR device 11, the scrubber 11a and the recovery tank 11d in the above-described third embodiment, and the scrubber 11a, the recovery tank 11d and the recovery tank 11d in the above-described fourth embodiment. The water treatment tank 18a of the water treatment device 18 was used as a supply destination device for the condensed water Wa, but the present invention is not limited to this. For example, the device to which the condensed water Wa is supplied in the present invention may be at least one selected from the scrubber 11a, the recovery tank 11d, and the water treatment tank 18a, or at least the EGR device 11 (scrubber 11a, It may include a demista 11b and a recovery tank 11d), may be onboard equipment other than the EGR device 11 and the water treatment device 18, or may be a combination thereof. Further, the number of devices to which the condensed water Wa is supplied in the present invention may be one or a plurality. Further, when the destination device for the condensed water Wa in the present invention is an onboard equipment other than the EGR device 11 and the water treatment device 18, the opening / closing drive of the first supply valve 15, the second supply valve 25, and the third supply valve 45 is performed. , The EGR device 11 may be controlled based on the above-mentioned detection result such as gas pressure regardless of whether or not the EGR device 11 is in operation, that is, regardless of the engine load of the engine body 2.

Further, in the fourth embodiment described above, when the water level of the water treatment tank 18a is less than the lower limit water level Lb and the gas pressure (for example, sweep pressure P) applied to the condensed water Wa is larger than the head differential pressure P (h1). , The first supply valve 15 and the second supply valve 25 were opened to pump and supply the condensed water Wa to the scrubber 11a and the recovery tank 11d, but the present invention is not limited thereto. For example, even if all the supply valves of the first supply valve 15, the second supply valve 25, and the third supply valve 45 that satisfy the condition that the gas pressure applied to the condensed water Wa is larger than the head differential pressure are opened. Alternatively, at least one supply valve selected from all these supply valves may be opened. In this case, the head differential pressure P (h1), which is the largest of the head differential pressures P (h1), P (h2), and P (h3), may be compared with the detected value of the gas pressure, or the head differential pressure may be compared. P (h1), P (h2), P (h3) may be sequentially compared with the detected value of the gas pressure.

Further, in the above-described first to fourth embodiments, the pressure detecting unit 16 for detecting the gas pressure applied to the condensed water Wa (the gas pressure used for pumping the condensed water Wa to the supply destination device) is the scavenging trunk of the engine body 2. Although it was arranged in 2b, the present invention is not limited to this. In the present invention, the location where the pressure detection unit 16 is arranged may be any location as long as it can detect the gas pressure, and may be, for example, a cooler 4 or a gas-liquid separation device 5. It may be the condensed water chamber 13, the collection pipe 12, or the air supply pipes 113 and 114.

Further, the gas pressure may be a sweep pressure of the engine body 2 that can be detected by the pressure detection unit 16, or is based on the relationship between the engine load and the pressure of the engine body 2 (hereinafter, referred to as the first relationship). It may be the scavenging pressure calculated by the above or the internal pressure of the condensed water chamber 13. For example, as the first relationship, there is a correlation between the engine load of the engine body 2 and the scavenging pressure, or a correlation between the engine load of the engine body 2 and the internal pressure of the condensed water chamber 13. Alternatively, the gas pressure may be a pressure obtained by correcting the scavenging pressure based on the relationship between the engine load and the pressure of the engine body 2 (hereinafter, referred to as the second relationship). For example, as the second relationship, there is a correlation between the engine load of the engine body 2 and the pressure correction value. The pressure correction value is a pressure corresponding to an error difference between the scavenging pressure of the engine body 2 and the internal pressure of the condensed water chamber 13. The corrected pressure can be calculated by correcting the sweep pressure of the engine body 2 (for example, the sweep pressure detected by the pressure detection unit 16) based on the pressure correction value derived according to the engine load. ..

Further, in the above-described first to fourth embodiments, the EGR device 11 provided with the recovery tank 11d separate from the demista 11b has been illustrated, but the present invention is not limited thereto. For example, the demista 11b may have a structure integrated with the recovery tank 11d, or may have a structure in which the scrubber water Wb used for cleaning the exhaust gas is separated and recovered from the recirculated gas and stored. ..

Further, in the above-described embodiments 3 and 4, the second water supply pipe 24 is branched from the first water supply pipe 14, or the second water supply pipe 24 and the third water supply pipe 44 are branched from the first water supply pipe 14. However, the present invention is not limited to this. For example, each inlet end of the first water supply pipe 14, the second water supply pipe 24, and the third water supply pipe 44 may be independently connected to the condensed water chamber 13.

Further, the present invention is not limited by the above-described first to fourth embodiments. The present invention also includes a configuration in which the above-mentioned components are appropriately combined. In addition, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on the above-described embodiments 1 to 4 are all included in the scope of the present invention.

1, 1A, 1B, 1C Marine diesel engine 2 Engine body 2a Cylinder 2b Sweeping trunk 2c Exhaust manifold 3 Supercharger 3a Compressor 3b Turbine 3c Rotating shaft 4 Cooler 5 Gas-liquid separator 6 Drain pipe 7 Outlet orifice 10, 20 , 30, 40 Exhaust gas treatment equipment 11 EGR equipment 11a Scrubber 11b Demista 11c EGR blower 11d Recovery tank 11e Recovery pipe 11f Pump 12 Collection pipe 12a First collection pipe 12b Second collection pipe 13 Condensed water chamber 14 First water supply pipe 15 First Supply valve 16 Pressure detection unit 17 Chamber water level detection unit 18 Water treatment device 18a Water treatment tank 18b Tank water level detection unit 19, 29, 39, 49 Control device 24 2nd water supply pipe 25 2nd supply valve 44 3rd water supply pipe 45 Third supply valve 101, 102 Exhaust pipe 111 Air supply part 112, 113, 114 Air supply pipe 121, 122 EGR pipe 131, 132 Circulation pipe Sa, Sb Liquid level Wa Condensed water Wb, Wc Scrubber water

Claims (14)

A supercharger that pressurizes and compresses the combustion gas, a cooler that cools the combustion gas after pressurization and compression, and a piston reciprocating by sweeping air in the cylinder and burning fuel using the combustion gas after cooling. An exhaust gas treatment device applied to a marine diesel engine equipped with an engine body for exercising.
An EGR device that cleans the exhaust gas discharged from the engine body with scrubber water and recirculates the washed exhaust gas as a part of the combustion gas.
A collection pipe that collects condensed water generated from the combustion gas after cooling by the cooler and gas pressure due to the combustion gas after cooling.
Through the collection pipe, a condensed water chamber for storing the condensed water and accumulating the gas pressure, and
A water supply pipe that communicates the condensed water chamber and the device to which the condensed water is supplied,
With
The condensed water is pressure-fed from the condensed water chamber to the supply destination device through the water supply pipe by utilizing the gas pressure accumulated in the condensed water chamber.
An exhaust gas treatment device characterized by this. The supply valve provided in the water supply pipe and
A pressure detector that detects the gas pressure and
The magnitude relationship between the head differential pressure, which is the pressure corresponding to the head difference between the water level of the condensed water chamber and the outlet water level of the water supply pipe, and the gas pressure detected by the pressure detecting unit was determined and detected. Control to control the supply valve to the open state when the gas pressure is larger than the head differential pressure, and to control the supply valve to the closed state when the detected gas pressure is equal to or lower than the head differential pressure. With the device
The exhaust gas treatment apparatus according to claim 1, further comprising. A plurality of the water supply pipes are provided so as to correspond to the plurality of destination devices so that the head difference with respect to the condensed water chamber is different from each other.
The supply valve is provided in each of the plurality of water supply pipes.
The control device supplies a plurality of the above-mentioned supplies based on the magnitude relationship between the head differential pressure between the water level of the condensed water chamber and the plurality of the water supply pipes and the gas pressure detected by the pressure detecting unit. Selectively control the open / closed state of the valve,
The exhaust gas treatment apparatus according to claim 2. A chamber water level detecting unit for detecting whether or not the water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber is provided.
When the detected water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber, the control device is in an open / closed state based on the magnitude relationship between the head differential pressure and the gas pressure for all the supply valves. When the water level of the condensed water chamber detected is less than the lower limit water level of the condensed water chamber, all the supply valves are controlled to be closed.
The exhaust gas treatment apparatus according to claim 2 or 3. It has a water treatment tank for collecting and purifying the scrubber water used for cleaning the exhaust gas, and purifies the scrubber water stored in the water treatment tank and supplies it to the EGR apparatus. Water treatment equipment and
A tank water level detection unit that detects the water level of the water treatment tank,
With
When the detected water level of the water treatment tank is less than the upper limit water level of the water treatment tank, the control device opens and closes all the supply valves based on the magnitude relationship between the head differential pressure and the gas pressure. When the state is controlled and the detected water level of the water treatment tank is equal to or higher than the upper limit water level of the water treatment tank, all the supply valves are controlled to be closed.
The exhaust gas treatment device according to any one of claims 2 to 4, wherein the exhaust gas treatment device is characterized. When the detected water level of the water treatment tank is less than the lower limit water level of the water treatment tank, the control device says that the gas pressure among the plurality of supply valves is larger than the head differential pressure. Control the open state of at least one of the supply valves satisfying the conditions.
The exhaust gas treatment apparatus according to claim 5, wherein the exhaust gas treatment apparatus according to claim 3 is cited. The gas pressure is the sweep pressure of the engine body, the sweep pressure calculated based on the relationship between the engine load and the pressure of the engine body, the internal pressure of the condensed water chamber, or the engine load and pressure of the engine body. It is the pressure corrected for the scavenging pressure based on the relationship with.
The exhaust gas treatment device according to any one of claims 1 to 6, wherein the exhaust gas treatment device is characterized. A supercharger that pressurizes and compresses the combustion gas, a cooler that cools the combustion gas after pressurization and compression, and a piston that reciprocates by sweeping air in the cylinder and burning fuel using the combustion gas after cooling. It is a water supply method applied to a marine diesel engine equipped with an engine body for exercising.
The condensed water generated from the combustion gas after cooling by the cooler and the gas pressure by the combustion gas after cooling are collected.
The collected condensed water is stored in the condensed water chamber, and the gas pressure is accumulated in the condensed water chamber.
Utilizing the gas pressure accumulated in the condensed water chamber, the condensed water is pumped from the condensed water chamber to a supply destination device through a water supply pipe.
A water supply method characterized by that. The gas pressure is detected by the pressure detector,
The magnitude relationship between the head differential pressure, which is the pressure corresponding to the head difference between the water level of the condensed water chamber and the outlet water level of the water supply pipe, and the gas pressure detected by the pressure detecting unit is determined.
When the detected gas pressure is larger than the head differential pressure, the supply valve of the water supply pipe is controlled to be open, and when the detected gas pressure is equal to or lower than the head differential pressure, the water supply pipe of the water supply pipe Control the supply valve to the closed state,
The water supply method according to claim 8, wherein the water supply method is characterized by the above. Based on the magnitude relationship between the head differential pressure between the water level of the condensed water chamber and the plurality of water supply pipes and the gas pressure detected by the pressure detecting unit, the open / closed state of the plurality of supply valves is determined. Selectively control
The plurality of water supply pipes are provided so as to correspond to the plurality of destination devices so that the head difference with respect to the condensed water chamber is different from each other.
The plurality of supply valves are provided in the plurality of water supply pipes, respectively.
The water supply method according to claim 9. Whether or not the water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber is detected by the chamber water level detection unit.
When the detected water level of the condensed water chamber is equal to or higher than the lower limit water level of the condensed water chamber, the open / closed state of all the supply valves is controlled and detected based on the magnitude relationship between the head differential pressure and the gas pressure. When the water level of the condensed water chamber is lower than the lower limit water level of the condensed water chamber, all the supply valves are controlled to be closed.
The water supply method according to claim 9 or 10. The water level of the water treatment tank for collecting and purifying the scrubber water used for cleaning the exhaust gas from the engine body is detected by the tank water level detector.
When the detected water level of the water treatment tank is less than the upper limit water level of the water treatment tank, the open / closed state of all the supply valves is controlled based on the magnitude relationship between the head differential pressure and the gas pressure. When the detected water level of the water treatment tank is equal to or higher than the upper limit water level of the water treatment tank, all the supply valves are controlled to be closed.
The water supply method according to any one of claims 9 to 11, characterized in that. When the detected water level of the water treatment tank is less than the lower limit water level of the water treatment tank, at least one of the plurality of supply valves satisfies the condition that the gas pressure is larger than the head differential pressure. Control the supply valve in the open state,
The water supply method according to claim 12, wherein claim 10 is cited. The gas pressure is the sweep pressure of the engine body, the sweep pressure calculated based on the relationship between the engine load and the pressure of the engine body, the internal pressure of the condensed water chamber, or the engine load and pressure of the engine body. It is the pressure corrected for the scavenging pressure based on the relationship with.
The water supply method according to any one of claims 8 to 13, wherein the water supply method is characterized.

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